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48debafe MP |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* | |
3 | * Copyright (C) 2018 Red Hat. All rights reserved. | |
4 | * | |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include <linux/device-mapper.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/init.h> | |
11 | #include <linux/vmalloc.h> | |
12 | #include <linux/kthread.h> | |
13 | #include <linux/dm-io.h> | |
14 | #include <linux/dm-kcopyd.h> | |
15 | #include <linux/dax.h> | |
16 | #include <linux/pfn_t.h> | |
17 | #include <linux/libnvdimm.h> | |
18 | ||
19 | #define DM_MSG_PREFIX "writecache" | |
20 | ||
21 | #define HIGH_WATERMARK 50 | |
22 | #define LOW_WATERMARK 45 | |
23 | #define MAX_WRITEBACK_JOBS 0 | |
24 | #define ENDIO_LATENCY 16 | |
25 | #define WRITEBACK_LATENCY 64 | |
26 | #define AUTOCOMMIT_BLOCKS_SSD 65536 | |
27 | #define AUTOCOMMIT_BLOCKS_PMEM 64 | |
28 | #define AUTOCOMMIT_MSEC 1000 | |
3923d485 MP |
29 | #define MAX_AGE_DIV 16 |
30 | #define MAX_AGE_UNSPECIFIED -1UL | |
48debafe MP |
31 | |
32 | #define BITMAP_GRANULARITY 65536 | |
33 | #if BITMAP_GRANULARITY < PAGE_SIZE | |
34 | #undef BITMAP_GRANULARITY | |
35 | #define BITMAP_GRANULARITY PAGE_SIZE | |
36 | #endif | |
37 | ||
38 | #if IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API) && IS_ENABLED(CONFIG_DAX_DRIVER) | |
39 | #define DM_WRITECACHE_HAS_PMEM | |
40 | #endif | |
41 | ||
42 | #ifdef DM_WRITECACHE_HAS_PMEM | |
43 | #define pmem_assign(dest, src) \ | |
44 | do { \ | |
45 | typeof(dest) uniq = (src); \ | |
46 | memcpy_flushcache(&(dest), &uniq, sizeof(dest)); \ | |
47 | } while (0) | |
48 | #else | |
49 | #define pmem_assign(dest, src) ((dest) = (src)) | |
50 | #endif | |
51 | ||
ec6347bb | 52 | #if IS_ENABLED(CONFIG_ARCH_HAS_COPY_MC) && defined(DM_WRITECACHE_HAS_PMEM) |
48debafe MP |
53 | #define DM_WRITECACHE_HANDLE_HARDWARE_ERRORS |
54 | #endif | |
55 | ||
56 | #define MEMORY_SUPERBLOCK_MAGIC 0x23489321 | |
57 | #define MEMORY_SUPERBLOCK_VERSION 1 | |
58 | ||
59 | struct wc_memory_entry { | |
60 | __le64 original_sector; | |
61 | __le64 seq_count; | |
62 | }; | |
63 | ||
64 | struct wc_memory_superblock { | |
65 | union { | |
66 | struct { | |
67 | __le32 magic; | |
68 | __le32 version; | |
69 | __le32 block_size; | |
70 | __le32 pad; | |
71 | __le64 n_blocks; | |
72 | __le64 seq_count; | |
73 | }; | |
74 | __le64 padding[8]; | |
75 | }; | |
c40819f2 | 76 | struct wc_memory_entry entries[]; |
48debafe MP |
77 | }; |
78 | ||
79 | struct wc_entry { | |
80 | struct rb_node rb_node; | |
81 | struct list_head lru; | |
82 | unsigned short wc_list_contiguous; | |
83 | bool write_in_progress | |
84 | #if BITS_PER_LONG == 64 | |
85 | :1 | |
86 | #endif | |
87 | ; | |
88 | unsigned long index | |
89 | #if BITS_PER_LONG == 64 | |
90 | :47 | |
91 | #endif | |
92 | ; | |
3923d485 | 93 | unsigned long age; |
48debafe MP |
94 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS |
95 | uint64_t original_sector; | |
96 | uint64_t seq_count; | |
97 | #endif | |
98 | }; | |
99 | ||
100 | #ifdef DM_WRITECACHE_HAS_PMEM | |
101 | #define WC_MODE_PMEM(wc) ((wc)->pmem_mode) | |
102 | #define WC_MODE_FUA(wc) ((wc)->writeback_fua) | |
103 | #else | |
104 | #define WC_MODE_PMEM(wc) false | |
105 | #define WC_MODE_FUA(wc) false | |
106 | #endif | |
107 | #define WC_MODE_SORT_FREELIST(wc) (!WC_MODE_PMEM(wc)) | |
108 | ||
109 | struct dm_writecache { | |
110 | struct mutex lock; | |
111 | struct list_head lru; | |
112 | union { | |
113 | struct list_head freelist; | |
114 | struct { | |
115 | struct rb_root freetree; | |
116 | struct wc_entry *current_free; | |
117 | }; | |
118 | }; | |
119 | struct rb_root tree; | |
120 | ||
121 | size_t freelist_size; | |
122 | size_t writeback_size; | |
123 | size_t freelist_high_watermark; | |
124 | size_t freelist_low_watermark; | |
3923d485 | 125 | unsigned long max_age; |
48debafe MP |
126 | |
127 | unsigned uncommitted_blocks; | |
128 | unsigned autocommit_blocks; | |
129 | unsigned max_writeback_jobs; | |
130 | ||
131 | int error; | |
132 | ||
133 | unsigned long autocommit_jiffies; | |
134 | struct timer_list autocommit_timer; | |
135 | struct wait_queue_head freelist_wait; | |
136 | ||
3923d485 MP |
137 | struct timer_list max_age_timer; |
138 | ||
48debafe MP |
139 | atomic_t bio_in_progress[2]; |
140 | struct wait_queue_head bio_in_progress_wait[2]; | |
141 | ||
142 | struct dm_target *ti; | |
143 | struct dm_dev *dev; | |
144 | struct dm_dev *ssd_dev; | |
d284f824 | 145 | sector_t start_sector; |
48debafe MP |
146 | void *memory_map; |
147 | uint64_t memory_map_size; | |
148 | size_t metadata_sectors; | |
149 | size_t n_blocks; | |
150 | uint64_t seq_count; | |
4134455f | 151 | sector_t data_device_sectors; |
48debafe MP |
152 | void *block_start; |
153 | struct wc_entry *entries; | |
154 | unsigned block_size; | |
155 | unsigned char block_size_bits; | |
156 | ||
157 | bool pmem_mode:1; | |
158 | bool writeback_fua:1; | |
159 | ||
160 | bool overwrote_committed:1; | |
161 | bool memory_vmapped:1; | |
162 | ||
054bee16 | 163 | bool start_sector_set:1; |
48debafe MP |
164 | bool high_wm_percent_set:1; |
165 | bool low_wm_percent_set:1; | |
166 | bool max_writeback_jobs_set:1; | |
167 | bool autocommit_blocks_set:1; | |
168 | bool autocommit_time_set:1; | |
054bee16 | 169 | bool max_age_set:1; |
48debafe MP |
170 | bool writeback_fua_set:1; |
171 | bool flush_on_suspend:1; | |
93de44eb | 172 | bool cleaner:1; |
054bee16 MP |
173 | bool cleaner_set:1; |
174 | ||
175 | unsigned high_wm_percent_value; | |
176 | unsigned low_wm_percent_value; | |
177 | unsigned autocommit_time_value; | |
178 | unsigned max_age_value; | |
48debafe MP |
179 | |
180 | unsigned writeback_all; | |
181 | struct workqueue_struct *writeback_wq; | |
182 | struct work_struct writeback_work; | |
183 | struct work_struct flush_work; | |
184 | ||
185 | struct dm_io_client *dm_io; | |
186 | ||
187 | raw_spinlock_t endio_list_lock; | |
188 | struct list_head endio_list; | |
189 | struct task_struct *endio_thread; | |
190 | ||
191 | struct task_struct *flush_thread; | |
192 | struct bio_list flush_list; | |
193 | ||
194 | struct dm_kcopyd_client *dm_kcopyd; | |
195 | unsigned long *dirty_bitmap; | |
196 | unsigned dirty_bitmap_size; | |
197 | ||
198 | struct bio_set bio_set; | |
199 | mempool_t copy_pool; | |
200 | }; | |
201 | ||
202 | #define WB_LIST_INLINE 16 | |
203 | ||
204 | struct writeback_struct { | |
205 | struct list_head endio_entry; | |
206 | struct dm_writecache *wc; | |
207 | struct wc_entry **wc_list; | |
208 | unsigned wc_list_n; | |
48debafe MP |
209 | struct wc_entry *wc_list_inline[WB_LIST_INLINE]; |
210 | struct bio bio; | |
211 | }; | |
212 | ||
213 | struct copy_struct { | |
214 | struct list_head endio_entry; | |
215 | struct dm_writecache *wc; | |
216 | struct wc_entry *e; | |
217 | unsigned n_entries; | |
218 | int error; | |
219 | }; | |
220 | ||
221 | DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(dm_writecache_throttle, | |
222 | "A percentage of time allocated for data copying"); | |
223 | ||
224 | static void wc_lock(struct dm_writecache *wc) | |
225 | { | |
226 | mutex_lock(&wc->lock); | |
227 | } | |
228 | ||
229 | static void wc_unlock(struct dm_writecache *wc) | |
230 | { | |
231 | mutex_unlock(&wc->lock); | |
232 | } | |
233 | ||
234 | #ifdef DM_WRITECACHE_HAS_PMEM | |
235 | static int persistent_memory_claim(struct dm_writecache *wc) | |
236 | { | |
237 | int r; | |
238 | loff_t s; | |
239 | long p, da; | |
240 | pfn_t pfn; | |
241 | int id; | |
242 | struct page **pages; | |
f9e040ef | 243 | sector_t offset; |
48debafe MP |
244 | |
245 | wc->memory_vmapped = false; | |
246 | ||
48debafe MP |
247 | s = wc->memory_map_size; |
248 | p = s >> PAGE_SHIFT; | |
249 | if (!p) { | |
250 | r = -EINVAL; | |
251 | goto err1; | |
252 | } | |
253 | if (p != s >> PAGE_SHIFT) { | |
254 | r = -EOVERFLOW; | |
255 | goto err1; | |
256 | } | |
257 | ||
f9e040ef MP |
258 | offset = get_start_sect(wc->ssd_dev->bdev); |
259 | if (offset & (PAGE_SIZE / 512 - 1)) { | |
260 | r = -EINVAL; | |
261 | goto err1; | |
262 | } | |
263 | offset >>= PAGE_SHIFT - 9; | |
264 | ||
48debafe MP |
265 | id = dax_read_lock(); |
266 | ||
f9e040ef | 267 | da = dax_direct_access(wc->ssd_dev->dax_dev, offset, p, &wc->memory_map, &pfn); |
48debafe MP |
268 | if (da < 0) { |
269 | wc->memory_map = NULL; | |
270 | r = da; | |
271 | goto err2; | |
272 | } | |
273 | if (!pfn_t_has_page(pfn)) { | |
274 | wc->memory_map = NULL; | |
275 | r = -EOPNOTSUPP; | |
276 | goto err2; | |
277 | } | |
278 | if (da != p) { | |
279 | long i; | |
280 | wc->memory_map = NULL; | |
50a7d3ba | 281 | pages = kvmalloc_array(p, sizeof(struct page *), GFP_KERNEL); |
48debafe MP |
282 | if (!pages) { |
283 | r = -ENOMEM; | |
284 | goto err2; | |
285 | } | |
286 | i = 0; | |
287 | do { | |
288 | long daa; | |
f9e040ef | 289 | daa = dax_direct_access(wc->ssd_dev->dax_dev, offset + i, p - i, |
f742267a | 290 | NULL, &pfn); |
48debafe MP |
291 | if (daa <= 0) { |
292 | r = daa ? daa : -EINVAL; | |
293 | goto err3; | |
294 | } | |
295 | if (!pfn_t_has_page(pfn)) { | |
296 | r = -EOPNOTSUPP; | |
297 | goto err3; | |
298 | } | |
299 | while (daa-- && i < p) { | |
300 | pages[i++] = pfn_t_to_page(pfn); | |
301 | pfn.val++; | |
d35bd764 MP |
302 | if (!(i & 15)) |
303 | cond_resched(); | |
48debafe MP |
304 | } |
305 | } while (i < p); | |
306 | wc->memory_map = vmap(pages, p, VM_MAP, PAGE_KERNEL); | |
307 | if (!wc->memory_map) { | |
308 | r = -ENOMEM; | |
309 | goto err3; | |
310 | } | |
311 | kvfree(pages); | |
312 | wc->memory_vmapped = true; | |
313 | } | |
314 | ||
315 | dax_read_unlock(id); | |
d284f824 MP |
316 | |
317 | wc->memory_map += (size_t)wc->start_sector << SECTOR_SHIFT; | |
318 | wc->memory_map_size -= (size_t)wc->start_sector << SECTOR_SHIFT; | |
319 | ||
48debafe MP |
320 | return 0; |
321 | err3: | |
322 | kvfree(pages); | |
323 | err2: | |
324 | dax_read_unlock(id); | |
325 | err1: | |
326 | return r; | |
327 | } | |
328 | #else | |
329 | static int persistent_memory_claim(struct dm_writecache *wc) | |
330 | { | |
857c4c0a | 331 | return -EOPNOTSUPP; |
48debafe MP |
332 | } |
333 | #endif | |
334 | ||
335 | static void persistent_memory_release(struct dm_writecache *wc) | |
336 | { | |
337 | if (wc->memory_vmapped) | |
d284f824 | 338 | vunmap(wc->memory_map - ((size_t)wc->start_sector << SECTOR_SHIFT)); |
48debafe MP |
339 | } |
340 | ||
341 | static struct page *persistent_memory_page(void *addr) | |
342 | { | |
343 | if (is_vmalloc_addr(addr)) | |
344 | return vmalloc_to_page(addr); | |
345 | else | |
346 | return virt_to_page(addr); | |
347 | } | |
348 | ||
349 | static unsigned persistent_memory_page_offset(void *addr) | |
350 | { | |
351 | return (unsigned long)addr & (PAGE_SIZE - 1); | |
352 | } | |
353 | ||
354 | static void persistent_memory_flush_cache(void *ptr, size_t size) | |
355 | { | |
356 | if (is_vmalloc_addr(ptr)) | |
357 | flush_kernel_vmap_range(ptr, size); | |
358 | } | |
359 | ||
360 | static void persistent_memory_invalidate_cache(void *ptr, size_t size) | |
361 | { | |
362 | if (is_vmalloc_addr(ptr)) | |
363 | invalidate_kernel_vmap_range(ptr, size); | |
364 | } | |
365 | ||
366 | static struct wc_memory_superblock *sb(struct dm_writecache *wc) | |
367 | { | |
368 | return wc->memory_map; | |
369 | } | |
370 | ||
371 | static struct wc_memory_entry *memory_entry(struct dm_writecache *wc, struct wc_entry *e) | |
372 | { | |
da4ad3a2 | 373 | return &sb(wc)->entries[e->index]; |
48debafe MP |
374 | } |
375 | ||
376 | static void *memory_data(struct dm_writecache *wc, struct wc_entry *e) | |
377 | { | |
378 | return (char *)wc->block_start + (e->index << wc->block_size_bits); | |
379 | } | |
380 | ||
381 | static sector_t cache_sector(struct dm_writecache *wc, struct wc_entry *e) | |
382 | { | |
d284f824 | 383 | return wc->start_sector + wc->metadata_sectors + |
48debafe MP |
384 | ((sector_t)e->index << (wc->block_size_bits - SECTOR_SHIFT)); |
385 | } | |
386 | ||
387 | static uint64_t read_original_sector(struct dm_writecache *wc, struct wc_entry *e) | |
388 | { | |
389 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
390 | return e->original_sector; | |
391 | #else | |
392 | return le64_to_cpu(memory_entry(wc, e)->original_sector); | |
393 | #endif | |
394 | } | |
395 | ||
396 | static uint64_t read_seq_count(struct dm_writecache *wc, struct wc_entry *e) | |
397 | { | |
398 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
399 | return e->seq_count; | |
400 | #else | |
401 | return le64_to_cpu(memory_entry(wc, e)->seq_count); | |
402 | #endif | |
403 | } | |
404 | ||
405 | static void clear_seq_count(struct dm_writecache *wc, struct wc_entry *e) | |
406 | { | |
407 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
408 | e->seq_count = -1; | |
409 | #endif | |
410 | pmem_assign(memory_entry(wc, e)->seq_count, cpu_to_le64(-1)); | |
411 | } | |
412 | ||
413 | static void write_original_sector_seq_count(struct dm_writecache *wc, struct wc_entry *e, | |
414 | uint64_t original_sector, uint64_t seq_count) | |
415 | { | |
416 | struct wc_memory_entry me; | |
417 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
418 | e->original_sector = original_sector; | |
419 | e->seq_count = seq_count; | |
420 | #endif | |
421 | me.original_sector = cpu_to_le64(original_sector); | |
422 | me.seq_count = cpu_to_le64(seq_count); | |
423 | pmem_assign(*memory_entry(wc, e), me); | |
424 | } | |
425 | ||
426 | #define writecache_error(wc, err, msg, arg...) \ | |
427 | do { \ | |
428 | if (!cmpxchg(&(wc)->error, 0, err)) \ | |
429 | DMERR(msg, ##arg); \ | |
430 | wake_up(&(wc)->freelist_wait); \ | |
431 | } while (0) | |
432 | ||
433 | #define writecache_has_error(wc) (unlikely(READ_ONCE((wc)->error))) | |
434 | ||
435 | static void writecache_flush_all_metadata(struct dm_writecache *wc) | |
436 | { | |
437 | if (!WC_MODE_PMEM(wc)) | |
438 | memset(wc->dirty_bitmap, -1, wc->dirty_bitmap_size); | |
439 | } | |
440 | ||
441 | static void writecache_flush_region(struct dm_writecache *wc, void *ptr, size_t size) | |
442 | { | |
443 | if (!WC_MODE_PMEM(wc)) | |
444 | __set_bit(((char *)ptr - (char *)wc->memory_map) / BITMAP_GRANULARITY, | |
445 | wc->dirty_bitmap); | |
446 | } | |
447 | ||
448 | static void writecache_disk_flush(struct dm_writecache *wc, struct dm_dev *dev); | |
449 | ||
450 | struct io_notify { | |
451 | struct dm_writecache *wc; | |
452 | struct completion c; | |
453 | atomic_t count; | |
454 | }; | |
455 | ||
456 | static void writecache_notify_io(unsigned long error, void *context) | |
457 | { | |
458 | struct io_notify *endio = context; | |
459 | ||
460 | if (unlikely(error != 0)) | |
461 | writecache_error(endio->wc, -EIO, "error writing metadata"); | |
462 | BUG_ON(atomic_read(&endio->count) <= 0); | |
463 | if (atomic_dec_and_test(&endio->count)) | |
464 | complete(&endio->c); | |
465 | } | |
466 | ||
aa950920 MP |
467 | static void writecache_wait_for_ios(struct dm_writecache *wc, int direction) |
468 | { | |
469 | wait_event(wc->bio_in_progress_wait[direction], | |
470 | !atomic_read(&wc->bio_in_progress[direction])); | |
471 | } | |
472 | ||
473 | static void ssd_commit_flushed(struct dm_writecache *wc, bool wait_for_ios) | |
48debafe MP |
474 | { |
475 | struct dm_io_region region; | |
476 | struct dm_io_request req; | |
477 | struct io_notify endio = { | |
478 | wc, | |
479 | COMPLETION_INITIALIZER_ONSTACK(endio.c), | |
480 | ATOMIC_INIT(1), | |
481 | }; | |
1e1132ea | 482 | unsigned bitmap_bits = wc->dirty_bitmap_size * 8; |
48debafe MP |
483 | unsigned i = 0; |
484 | ||
485 | while (1) { | |
486 | unsigned j; | |
487 | i = find_next_bit(wc->dirty_bitmap, bitmap_bits, i); | |
488 | if (unlikely(i == bitmap_bits)) | |
489 | break; | |
490 | j = find_next_zero_bit(wc->dirty_bitmap, bitmap_bits, i); | |
491 | ||
492 | region.bdev = wc->ssd_dev->bdev; | |
493 | region.sector = (sector_t)i * (BITMAP_GRANULARITY >> SECTOR_SHIFT); | |
494 | region.count = (sector_t)(j - i) * (BITMAP_GRANULARITY >> SECTOR_SHIFT); | |
495 | ||
496 | if (unlikely(region.sector >= wc->metadata_sectors)) | |
497 | break; | |
498 | if (unlikely(region.sector + region.count > wc->metadata_sectors)) | |
499 | region.count = wc->metadata_sectors - region.sector; | |
500 | ||
d284f824 | 501 | region.sector += wc->start_sector; |
48debafe MP |
502 | atomic_inc(&endio.count); |
503 | req.bi_op = REQ_OP_WRITE; | |
504 | req.bi_op_flags = REQ_SYNC; | |
505 | req.mem.type = DM_IO_VMA; | |
506 | req.mem.ptr.vma = (char *)wc->memory_map + (size_t)i * BITMAP_GRANULARITY; | |
507 | req.client = wc->dm_io; | |
508 | req.notify.fn = writecache_notify_io; | |
509 | req.notify.context = &endio; | |
510 | ||
511 | /* writing via async dm-io (implied by notify.fn above) won't return an error */ | |
512 | (void) dm_io(&req, 1, ®ion, NULL); | |
513 | i = j; | |
514 | } | |
515 | ||
516 | writecache_notify_io(0, &endio); | |
517 | wait_for_completion_io(&endio.c); | |
518 | ||
aa950920 MP |
519 | if (wait_for_ios) |
520 | writecache_wait_for_ios(wc, WRITE); | |
521 | ||
48debafe MP |
522 | writecache_disk_flush(wc, wc->ssd_dev); |
523 | ||
524 | memset(wc->dirty_bitmap, 0, wc->dirty_bitmap_size); | |
525 | } | |
526 | ||
dc8a01ae MP |
527 | static void ssd_commit_superblock(struct dm_writecache *wc) |
528 | { | |
529 | int r; | |
530 | struct dm_io_region region; | |
531 | struct dm_io_request req; | |
532 | ||
533 | region.bdev = wc->ssd_dev->bdev; | |
534 | region.sector = 0; | |
cb728484 | 535 | region.count = PAGE_SIZE >> SECTOR_SHIFT; |
dc8a01ae MP |
536 | |
537 | if (unlikely(region.sector + region.count > wc->metadata_sectors)) | |
538 | region.count = wc->metadata_sectors - region.sector; | |
539 | ||
540 | region.sector += wc->start_sector; | |
541 | ||
542 | req.bi_op = REQ_OP_WRITE; | |
543 | req.bi_op_flags = REQ_SYNC | REQ_FUA; | |
544 | req.mem.type = DM_IO_VMA; | |
545 | req.mem.ptr.vma = (char *)wc->memory_map; | |
546 | req.client = wc->dm_io; | |
547 | req.notify.fn = NULL; | |
548 | req.notify.context = NULL; | |
549 | ||
550 | r = dm_io(&req, 1, ®ion, NULL); | |
551 | if (unlikely(r)) | |
552 | writecache_error(wc, r, "error writing superblock"); | |
553 | } | |
554 | ||
aa950920 | 555 | static void writecache_commit_flushed(struct dm_writecache *wc, bool wait_for_ios) |
48debafe MP |
556 | { |
557 | if (WC_MODE_PMEM(wc)) | |
3e79f082 | 558 | pmem_wmb(); |
48debafe | 559 | else |
aa950920 | 560 | ssd_commit_flushed(wc, wait_for_ios); |
48debafe MP |
561 | } |
562 | ||
563 | static void writecache_disk_flush(struct dm_writecache *wc, struct dm_dev *dev) | |
564 | { | |
565 | int r; | |
566 | struct dm_io_region region; | |
567 | struct dm_io_request req; | |
568 | ||
569 | region.bdev = dev->bdev; | |
570 | region.sector = 0; | |
571 | region.count = 0; | |
572 | req.bi_op = REQ_OP_WRITE; | |
573 | req.bi_op_flags = REQ_PREFLUSH; | |
574 | req.mem.type = DM_IO_KMEM; | |
575 | req.mem.ptr.addr = NULL; | |
576 | req.client = wc->dm_io; | |
577 | req.notify.fn = NULL; | |
578 | ||
579 | r = dm_io(&req, 1, ®ion, NULL); | |
580 | if (unlikely(r)) | |
581 | writecache_error(wc, r, "error flushing metadata: %d", r); | |
582 | } | |
583 | ||
48debafe MP |
584 | #define WFE_RETURN_FOLLOWING 1 |
585 | #define WFE_LOWEST_SEQ 2 | |
586 | ||
587 | static struct wc_entry *writecache_find_entry(struct dm_writecache *wc, | |
588 | uint64_t block, int flags) | |
589 | { | |
590 | struct wc_entry *e; | |
591 | struct rb_node *node = wc->tree.rb_node; | |
592 | ||
593 | if (unlikely(!node)) | |
594 | return NULL; | |
595 | ||
596 | while (1) { | |
597 | e = container_of(node, struct wc_entry, rb_node); | |
598 | if (read_original_sector(wc, e) == block) | |
599 | break; | |
f8011d33 | 600 | |
48debafe MP |
601 | node = (read_original_sector(wc, e) >= block ? |
602 | e->rb_node.rb_left : e->rb_node.rb_right); | |
603 | if (unlikely(!node)) { | |
f8011d33 | 604 | if (!(flags & WFE_RETURN_FOLLOWING)) |
48debafe | 605 | return NULL; |
48debafe | 606 | if (read_original_sector(wc, e) >= block) { |
f8011d33 | 607 | return e; |
48debafe MP |
608 | } else { |
609 | node = rb_next(&e->rb_node); | |
f8011d33 | 610 | if (unlikely(!node)) |
48debafe | 611 | return NULL; |
48debafe | 612 | e = container_of(node, struct wc_entry, rb_node); |
f8011d33 | 613 | return e; |
48debafe MP |
614 | } |
615 | } | |
616 | } | |
617 | ||
618 | while (1) { | |
619 | struct wc_entry *e2; | |
620 | if (flags & WFE_LOWEST_SEQ) | |
621 | node = rb_prev(&e->rb_node); | |
622 | else | |
623 | node = rb_next(&e->rb_node); | |
84420b1e | 624 | if (unlikely(!node)) |
48debafe MP |
625 | return e; |
626 | e2 = container_of(node, struct wc_entry, rb_node); | |
627 | if (read_original_sector(wc, e2) != block) | |
628 | return e; | |
629 | e = e2; | |
630 | } | |
631 | } | |
632 | ||
633 | static void writecache_insert_entry(struct dm_writecache *wc, struct wc_entry *ins) | |
634 | { | |
635 | struct wc_entry *e; | |
636 | struct rb_node **node = &wc->tree.rb_node, *parent = NULL; | |
637 | ||
638 | while (*node) { | |
639 | e = container_of(*node, struct wc_entry, rb_node); | |
640 | parent = &e->rb_node; | |
641 | if (read_original_sector(wc, e) > read_original_sector(wc, ins)) | |
642 | node = &parent->rb_left; | |
643 | else | |
644 | node = &parent->rb_right; | |
645 | } | |
646 | rb_link_node(&ins->rb_node, parent, node); | |
647 | rb_insert_color(&ins->rb_node, &wc->tree); | |
648 | list_add(&ins->lru, &wc->lru); | |
3923d485 | 649 | ins->age = jiffies; |
48debafe MP |
650 | } |
651 | ||
652 | static void writecache_unlink(struct dm_writecache *wc, struct wc_entry *e) | |
653 | { | |
654 | list_del(&e->lru); | |
655 | rb_erase(&e->rb_node, &wc->tree); | |
656 | } | |
657 | ||
658 | static void writecache_add_to_freelist(struct dm_writecache *wc, struct wc_entry *e) | |
659 | { | |
660 | if (WC_MODE_SORT_FREELIST(wc)) { | |
661 | struct rb_node **node = &wc->freetree.rb_node, *parent = NULL; | |
662 | if (unlikely(!*node)) | |
663 | wc->current_free = e; | |
664 | while (*node) { | |
665 | parent = *node; | |
666 | if (&e->rb_node < *node) | |
667 | node = &parent->rb_left; | |
668 | else | |
669 | node = &parent->rb_right; | |
670 | } | |
671 | rb_link_node(&e->rb_node, parent, node); | |
672 | rb_insert_color(&e->rb_node, &wc->freetree); | |
673 | } else { | |
674 | list_add_tail(&e->lru, &wc->freelist); | |
675 | } | |
676 | wc->freelist_size++; | |
677 | } | |
678 | ||
41c526c5 MP |
679 | static inline void writecache_verify_watermark(struct dm_writecache *wc) |
680 | { | |
681 | if (unlikely(wc->freelist_size + wc->writeback_size <= wc->freelist_high_watermark)) | |
682 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
683 | } | |
684 | ||
3923d485 MP |
685 | static void writecache_max_age_timer(struct timer_list *t) |
686 | { | |
687 | struct dm_writecache *wc = from_timer(wc, t, max_age_timer); | |
688 | ||
689 | if (!dm_suspended(wc->ti) && !writecache_has_error(wc)) { | |
690 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
691 | mod_timer(&wc->max_age_timer, jiffies + wc->max_age / MAX_AGE_DIV); | |
692 | } | |
693 | } | |
694 | ||
dcd19507 | 695 | static struct wc_entry *writecache_pop_from_freelist(struct dm_writecache *wc, sector_t expected_sector) |
48debafe MP |
696 | { |
697 | struct wc_entry *e; | |
698 | ||
699 | if (WC_MODE_SORT_FREELIST(wc)) { | |
700 | struct rb_node *next; | |
701 | if (unlikely(!wc->current_free)) | |
702 | return NULL; | |
703 | e = wc->current_free; | |
dcd19507 MP |
704 | if (expected_sector != (sector_t)-1 && unlikely(cache_sector(wc, e) != expected_sector)) |
705 | return NULL; | |
48debafe MP |
706 | next = rb_next(&e->rb_node); |
707 | rb_erase(&e->rb_node, &wc->freetree); | |
708 | if (unlikely(!next)) | |
709 | next = rb_first(&wc->freetree); | |
710 | wc->current_free = next ? container_of(next, struct wc_entry, rb_node) : NULL; | |
711 | } else { | |
712 | if (unlikely(list_empty(&wc->freelist))) | |
713 | return NULL; | |
714 | e = container_of(wc->freelist.next, struct wc_entry, lru); | |
dcd19507 MP |
715 | if (expected_sector != (sector_t)-1 && unlikely(cache_sector(wc, e) != expected_sector)) |
716 | return NULL; | |
48debafe MP |
717 | list_del(&e->lru); |
718 | } | |
719 | wc->freelist_size--; | |
41c526c5 MP |
720 | |
721 | writecache_verify_watermark(wc); | |
48debafe MP |
722 | |
723 | return e; | |
724 | } | |
725 | ||
726 | static void writecache_free_entry(struct dm_writecache *wc, struct wc_entry *e) | |
727 | { | |
728 | writecache_unlink(wc, e); | |
729 | writecache_add_to_freelist(wc, e); | |
730 | clear_seq_count(wc, e); | |
731 | writecache_flush_region(wc, memory_entry(wc, e), sizeof(struct wc_memory_entry)); | |
732 | if (unlikely(waitqueue_active(&wc->freelist_wait))) | |
733 | wake_up(&wc->freelist_wait); | |
734 | } | |
735 | ||
736 | static void writecache_wait_on_freelist(struct dm_writecache *wc) | |
737 | { | |
738 | DEFINE_WAIT(wait); | |
739 | ||
740 | prepare_to_wait(&wc->freelist_wait, &wait, TASK_UNINTERRUPTIBLE); | |
741 | wc_unlock(wc); | |
742 | io_schedule(); | |
743 | finish_wait(&wc->freelist_wait, &wait); | |
744 | wc_lock(wc); | |
745 | } | |
746 | ||
747 | static void writecache_poison_lists(struct dm_writecache *wc) | |
748 | { | |
749 | /* | |
750 | * Catch incorrect access to these values while the device is suspended. | |
751 | */ | |
752 | memset(&wc->tree, -1, sizeof wc->tree); | |
753 | wc->lru.next = LIST_POISON1; | |
754 | wc->lru.prev = LIST_POISON2; | |
755 | wc->freelist.next = LIST_POISON1; | |
756 | wc->freelist.prev = LIST_POISON2; | |
757 | } | |
758 | ||
759 | static void writecache_flush_entry(struct dm_writecache *wc, struct wc_entry *e) | |
760 | { | |
761 | writecache_flush_region(wc, memory_entry(wc, e), sizeof(struct wc_memory_entry)); | |
762 | if (WC_MODE_PMEM(wc)) | |
763 | writecache_flush_region(wc, memory_data(wc, e), wc->block_size); | |
764 | } | |
765 | ||
766 | static bool writecache_entry_is_committed(struct dm_writecache *wc, struct wc_entry *e) | |
767 | { | |
768 | return read_seq_count(wc, e) < wc->seq_count; | |
769 | } | |
770 | ||
771 | static void writecache_flush(struct dm_writecache *wc) | |
772 | { | |
773 | struct wc_entry *e, *e2; | |
774 | bool need_flush_after_free; | |
775 | ||
776 | wc->uncommitted_blocks = 0; | |
777 | del_timer(&wc->autocommit_timer); | |
778 | ||
779 | if (list_empty(&wc->lru)) | |
780 | return; | |
781 | ||
782 | e = container_of(wc->lru.next, struct wc_entry, lru); | |
783 | if (writecache_entry_is_committed(wc, e)) { | |
784 | if (wc->overwrote_committed) { | |
785 | writecache_wait_for_ios(wc, WRITE); | |
786 | writecache_disk_flush(wc, wc->ssd_dev); | |
787 | wc->overwrote_committed = false; | |
788 | } | |
789 | return; | |
790 | } | |
791 | while (1) { | |
792 | writecache_flush_entry(wc, e); | |
793 | if (unlikely(e->lru.next == &wc->lru)) | |
794 | break; | |
795 | e2 = container_of(e->lru.next, struct wc_entry, lru); | |
796 | if (writecache_entry_is_committed(wc, e2)) | |
797 | break; | |
798 | e = e2; | |
799 | cond_resched(); | |
800 | } | |
aa950920 | 801 | writecache_commit_flushed(wc, true); |
48debafe MP |
802 | |
803 | wc->seq_count++; | |
804 | pmem_assign(sb(wc)->seq_count, cpu_to_le64(wc->seq_count)); | |
dc8a01ae MP |
805 | if (WC_MODE_PMEM(wc)) |
806 | writecache_commit_flushed(wc, false); | |
807 | else | |
808 | ssd_commit_superblock(wc); | |
48debafe MP |
809 | |
810 | wc->overwrote_committed = false; | |
811 | ||
812 | need_flush_after_free = false; | |
813 | while (1) { | |
814 | /* Free another committed entry with lower seq-count */ | |
815 | struct rb_node *rb_node = rb_prev(&e->rb_node); | |
816 | ||
817 | if (rb_node) { | |
818 | e2 = container_of(rb_node, struct wc_entry, rb_node); | |
819 | if (read_original_sector(wc, e2) == read_original_sector(wc, e) && | |
820 | likely(!e2->write_in_progress)) { | |
821 | writecache_free_entry(wc, e2); | |
822 | need_flush_after_free = true; | |
823 | } | |
824 | } | |
825 | if (unlikely(e->lru.prev == &wc->lru)) | |
826 | break; | |
827 | e = container_of(e->lru.prev, struct wc_entry, lru); | |
828 | cond_resched(); | |
829 | } | |
830 | ||
831 | if (need_flush_after_free) | |
aa950920 | 832 | writecache_commit_flushed(wc, false); |
48debafe MP |
833 | } |
834 | ||
835 | static void writecache_flush_work(struct work_struct *work) | |
836 | { | |
837 | struct dm_writecache *wc = container_of(work, struct dm_writecache, flush_work); | |
838 | ||
839 | wc_lock(wc); | |
840 | writecache_flush(wc); | |
841 | wc_unlock(wc); | |
842 | } | |
843 | ||
844 | static void writecache_autocommit_timer(struct timer_list *t) | |
845 | { | |
846 | struct dm_writecache *wc = from_timer(wc, t, autocommit_timer); | |
847 | if (!writecache_has_error(wc)) | |
848 | queue_work(wc->writeback_wq, &wc->flush_work); | |
849 | } | |
850 | ||
851 | static void writecache_schedule_autocommit(struct dm_writecache *wc) | |
852 | { | |
853 | if (!timer_pending(&wc->autocommit_timer)) | |
854 | mod_timer(&wc->autocommit_timer, jiffies + wc->autocommit_jiffies); | |
855 | } | |
856 | ||
857 | static void writecache_discard(struct dm_writecache *wc, sector_t start, sector_t end) | |
858 | { | |
859 | struct wc_entry *e; | |
860 | bool discarded_something = false; | |
861 | ||
862 | e = writecache_find_entry(wc, start, WFE_RETURN_FOLLOWING | WFE_LOWEST_SEQ); | |
863 | if (unlikely(!e)) | |
864 | return; | |
865 | ||
866 | while (read_original_sector(wc, e) < end) { | |
867 | struct rb_node *node = rb_next(&e->rb_node); | |
868 | ||
869 | if (likely(!e->write_in_progress)) { | |
870 | if (!discarded_something) { | |
a143e172 HY |
871 | if (!WC_MODE_PMEM(wc)) { |
872 | writecache_wait_for_ios(wc, READ); | |
873 | writecache_wait_for_ios(wc, WRITE); | |
874 | } | |
48debafe MP |
875 | discarded_something = true; |
876 | } | |
39495b12 HY |
877 | if (!writecache_entry_is_committed(wc, e)) |
878 | wc->uncommitted_blocks--; | |
48debafe MP |
879 | writecache_free_entry(wc, e); |
880 | } | |
881 | ||
84420b1e | 882 | if (unlikely(!node)) |
48debafe MP |
883 | break; |
884 | ||
885 | e = container_of(node, struct wc_entry, rb_node); | |
886 | } | |
887 | ||
888 | if (discarded_something) | |
aa950920 | 889 | writecache_commit_flushed(wc, false); |
48debafe MP |
890 | } |
891 | ||
892 | static bool writecache_wait_for_writeback(struct dm_writecache *wc) | |
893 | { | |
894 | if (wc->writeback_size) { | |
895 | writecache_wait_on_freelist(wc); | |
896 | return true; | |
897 | } | |
898 | return false; | |
899 | } | |
900 | ||
901 | static void writecache_suspend(struct dm_target *ti) | |
902 | { | |
903 | struct dm_writecache *wc = ti->private; | |
904 | bool flush_on_suspend; | |
905 | ||
906 | del_timer_sync(&wc->autocommit_timer); | |
3923d485 | 907 | del_timer_sync(&wc->max_age_timer); |
48debafe MP |
908 | |
909 | wc_lock(wc); | |
910 | writecache_flush(wc); | |
911 | flush_on_suspend = wc->flush_on_suspend; | |
912 | if (flush_on_suspend) { | |
913 | wc->flush_on_suspend = false; | |
914 | wc->writeback_all++; | |
915 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
916 | } | |
917 | wc_unlock(wc); | |
918 | ||
adc0daad | 919 | drain_workqueue(wc->writeback_wq); |
48debafe MP |
920 | |
921 | wc_lock(wc); | |
922 | if (flush_on_suspend) | |
923 | wc->writeback_all--; | |
924 | while (writecache_wait_for_writeback(wc)); | |
925 | ||
926 | if (WC_MODE_PMEM(wc)) | |
927 | persistent_memory_flush_cache(wc->memory_map, wc->memory_map_size); | |
928 | ||
929 | writecache_poison_lists(wc); | |
930 | ||
931 | wc_unlock(wc); | |
932 | } | |
933 | ||
934 | static int writecache_alloc_entries(struct dm_writecache *wc) | |
935 | { | |
936 | size_t b; | |
937 | ||
938 | if (wc->entries) | |
939 | return 0; | |
50a7d3ba | 940 | wc->entries = vmalloc(array_size(sizeof(struct wc_entry), wc->n_blocks)); |
48debafe MP |
941 | if (!wc->entries) |
942 | return -ENOMEM; | |
943 | for (b = 0; b < wc->n_blocks; b++) { | |
944 | struct wc_entry *e = &wc->entries[b]; | |
945 | e->index = b; | |
946 | e->write_in_progress = false; | |
1edaa447 | 947 | cond_resched(); |
48debafe MP |
948 | } |
949 | ||
950 | return 0; | |
951 | } | |
952 | ||
31b22120 MP |
953 | static int writecache_read_metadata(struct dm_writecache *wc, sector_t n_sectors) |
954 | { | |
955 | struct dm_io_region region; | |
956 | struct dm_io_request req; | |
957 | ||
958 | region.bdev = wc->ssd_dev->bdev; | |
959 | region.sector = wc->start_sector; | |
960 | region.count = n_sectors; | |
961 | req.bi_op = REQ_OP_READ; | |
962 | req.bi_op_flags = REQ_SYNC; | |
963 | req.mem.type = DM_IO_VMA; | |
964 | req.mem.ptr.vma = (char *)wc->memory_map; | |
965 | req.client = wc->dm_io; | |
966 | req.notify.fn = NULL; | |
967 | ||
968 | return dm_io(&req, 1, ®ion, NULL); | |
969 | } | |
970 | ||
48debafe MP |
971 | static void writecache_resume(struct dm_target *ti) |
972 | { | |
973 | struct dm_writecache *wc = ti->private; | |
974 | size_t b; | |
975 | bool need_flush = false; | |
976 | __le64 sb_seq_count; | |
977 | int r; | |
978 | ||
979 | wc_lock(wc); | |
980 | ||
d9928ac5 | 981 | wc->data_device_sectors = bdev_nr_sectors(wc->dev->bdev); |
4134455f | 982 | |
31b22120 | 983 | if (WC_MODE_PMEM(wc)) { |
48debafe | 984 | persistent_memory_invalidate_cache(wc->memory_map, wc->memory_map_size); |
31b22120 MP |
985 | } else { |
986 | r = writecache_read_metadata(wc, wc->metadata_sectors); | |
987 | if (r) { | |
988 | size_t sb_entries_offset; | |
989 | writecache_error(wc, r, "unable to read metadata: %d", r); | |
990 | sb_entries_offset = offsetof(struct wc_memory_superblock, entries); | |
991 | memset((char *)wc->memory_map + sb_entries_offset, -1, | |
992 | (wc->metadata_sectors << SECTOR_SHIFT) - sb_entries_offset); | |
993 | } | |
994 | } | |
48debafe MP |
995 | |
996 | wc->tree = RB_ROOT; | |
997 | INIT_LIST_HEAD(&wc->lru); | |
998 | if (WC_MODE_SORT_FREELIST(wc)) { | |
999 | wc->freetree = RB_ROOT; | |
1000 | wc->current_free = NULL; | |
1001 | } else { | |
1002 | INIT_LIST_HEAD(&wc->freelist); | |
1003 | } | |
1004 | wc->freelist_size = 0; | |
1005 | ||
ec6347bb DW |
1006 | r = copy_mc_to_kernel(&sb_seq_count, &sb(wc)->seq_count, |
1007 | sizeof(uint64_t)); | |
48debafe MP |
1008 | if (r) { |
1009 | writecache_error(wc, r, "hardware memory error when reading superblock: %d", r); | |
1010 | sb_seq_count = cpu_to_le64(0); | |
1011 | } | |
1012 | wc->seq_count = le64_to_cpu(sb_seq_count); | |
1013 | ||
1014 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
1015 | for (b = 0; b < wc->n_blocks; b++) { | |
1016 | struct wc_entry *e = &wc->entries[b]; | |
1017 | struct wc_memory_entry wme; | |
1018 | if (writecache_has_error(wc)) { | |
1019 | e->original_sector = -1; | |
1020 | e->seq_count = -1; | |
1021 | continue; | |
1022 | } | |
ec6347bb DW |
1023 | r = copy_mc_to_kernel(&wme, memory_entry(wc, e), |
1024 | sizeof(struct wc_memory_entry)); | |
48debafe MP |
1025 | if (r) { |
1026 | writecache_error(wc, r, "hardware memory error when reading metadata entry %lu: %d", | |
1027 | (unsigned long)b, r); | |
1028 | e->original_sector = -1; | |
1029 | e->seq_count = -1; | |
1030 | } else { | |
1031 | e->original_sector = le64_to_cpu(wme.original_sector); | |
1032 | e->seq_count = le64_to_cpu(wme.seq_count); | |
1033 | } | |
1edaa447 | 1034 | cond_resched(); |
48debafe MP |
1035 | } |
1036 | #endif | |
1037 | for (b = 0; b < wc->n_blocks; b++) { | |
1038 | struct wc_entry *e = &wc->entries[b]; | |
1039 | if (!writecache_entry_is_committed(wc, e)) { | |
1040 | if (read_seq_count(wc, e) != -1) { | |
1041 | erase_this: | |
1042 | clear_seq_count(wc, e); | |
1043 | need_flush = true; | |
1044 | } | |
1045 | writecache_add_to_freelist(wc, e); | |
1046 | } else { | |
1047 | struct wc_entry *old; | |
1048 | ||
1049 | old = writecache_find_entry(wc, read_original_sector(wc, e), 0); | |
1050 | if (!old) { | |
1051 | writecache_insert_entry(wc, e); | |
1052 | } else { | |
1053 | if (read_seq_count(wc, old) == read_seq_count(wc, e)) { | |
1054 | writecache_error(wc, -EINVAL, | |
1055 | "two identical entries, position %llu, sector %llu, sequence %llu", | |
1056 | (unsigned long long)b, (unsigned long long)read_original_sector(wc, e), | |
1057 | (unsigned long long)read_seq_count(wc, e)); | |
1058 | } | |
1059 | if (read_seq_count(wc, old) > read_seq_count(wc, e)) { | |
1060 | goto erase_this; | |
1061 | } else { | |
1062 | writecache_free_entry(wc, old); | |
1063 | writecache_insert_entry(wc, e); | |
1064 | need_flush = true; | |
1065 | } | |
1066 | } | |
1067 | } | |
1068 | cond_resched(); | |
1069 | } | |
1070 | ||
1071 | if (need_flush) { | |
1072 | writecache_flush_all_metadata(wc); | |
aa950920 | 1073 | writecache_commit_flushed(wc, false); |
48debafe MP |
1074 | } |
1075 | ||
41c526c5 MP |
1076 | writecache_verify_watermark(wc); |
1077 | ||
3923d485 MP |
1078 | if (wc->max_age != MAX_AGE_UNSPECIFIED) |
1079 | mod_timer(&wc->max_age_timer, jiffies + wc->max_age / MAX_AGE_DIV); | |
1080 | ||
48debafe MP |
1081 | wc_unlock(wc); |
1082 | } | |
1083 | ||
1084 | static int process_flush_mesg(unsigned argc, char **argv, struct dm_writecache *wc) | |
1085 | { | |
1086 | if (argc != 1) | |
1087 | return -EINVAL; | |
1088 | ||
1089 | wc_lock(wc); | |
1090 | if (dm_suspended(wc->ti)) { | |
1091 | wc_unlock(wc); | |
1092 | return -EBUSY; | |
1093 | } | |
1094 | if (writecache_has_error(wc)) { | |
1095 | wc_unlock(wc); | |
1096 | return -EIO; | |
1097 | } | |
1098 | ||
1099 | writecache_flush(wc); | |
1100 | wc->writeback_all++; | |
1101 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
1102 | wc_unlock(wc); | |
1103 | ||
1104 | flush_workqueue(wc->writeback_wq); | |
1105 | ||
1106 | wc_lock(wc); | |
1107 | wc->writeback_all--; | |
1108 | if (writecache_has_error(wc)) { | |
1109 | wc_unlock(wc); | |
1110 | return -EIO; | |
1111 | } | |
1112 | wc_unlock(wc); | |
1113 | ||
1114 | return 0; | |
1115 | } | |
1116 | ||
1117 | static int process_flush_on_suspend_mesg(unsigned argc, char **argv, struct dm_writecache *wc) | |
1118 | { | |
1119 | if (argc != 1) | |
1120 | return -EINVAL; | |
1121 | ||
1122 | wc_lock(wc); | |
1123 | wc->flush_on_suspend = true; | |
1124 | wc_unlock(wc); | |
1125 | ||
1126 | return 0; | |
1127 | } | |
1128 | ||
93de44eb MP |
1129 | static void activate_cleaner(struct dm_writecache *wc) |
1130 | { | |
1131 | wc->flush_on_suspend = true; | |
1132 | wc->cleaner = true; | |
1133 | wc->freelist_high_watermark = wc->n_blocks; | |
1134 | wc->freelist_low_watermark = wc->n_blocks; | |
1135 | } | |
1136 | ||
1137 | static int process_cleaner_mesg(unsigned argc, char **argv, struct dm_writecache *wc) | |
1138 | { | |
1139 | if (argc != 1) | |
1140 | return -EINVAL; | |
1141 | ||
1142 | wc_lock(wc); | |
1143 | activate_cleaner(wc); | |
1144 | if (!dm_suspended(wc->ti)) | |
1145 | writecache_verify_watermark(wc); | |
1146 | wc_unlock(wc); | |
1147 | ||
1148 | return 0; | |
1149 | } | |
1150 | ||
48debafe MP |
1151 | static int writecache_message(struct dm_target *ti, unsigned argc, char **argv, |
1152 | char *result, unsigned maxlen) | |
1153 | { | |
1154 | int r = -EINVAL; | |
1155 | struct dm_writecache *wc = ti->private; | |
1156 | ||
1157 | if (!strcasecmp(argv[0], "flush")) | |
1158 | r = process_flush_mesg(argc, argv, wc); | |
1159 | else if (!strcasecmp(argv[0], "flush_on_suspend")) | |
1160 | r = process_flush_on_suspend_mesg(argc, argv, wc); | |
93de44eb MP |
1161 | else if (!strcasecmp(argv[0], "cleaner")) |
1162 | r = process_cleaner_mesg(argc, argv, wc); | |
48debafe MP |
1163 | else |
1164 | DMERR("unrecognised message received: %s", argv[0]); | |
1165 | ||
1166 | return r; | |
1167 | } | |
1168 | ||
48338daa MP |
1169 | static void memcpy_flushcache_optimized(void *dest, void *source, size_t size) |
1170 | { | |
1171 | /* | |
1172 | * clflushopt performs better with block size 1024, 2048, 4096 | |
1173 | * non-temporal stores perform better with block size 512 | |
1174 | * | |
1175 | * block size 512 1024 2048 4096 | |
1176 | * movnti 496 MB/s 642 MB/s 725 MB/s 744 MB/s | |
1177 | * clflushopt 373 MB/s 688 MB/s 1.1 GB/s 1.2 GB/s | |
1178 | * | |
1179 | * We see that movnti performs better for 512-byte blocks, and | |
1180 | * clflushopt performs better for 1024-byte and larger blocks. So, we | |
1181 | * prefer clflushopt for sizes >= 768. | |
1182 | * | |
1183 | * NOTE: this happens to be the case now (with dm-writecache's single | |
1184 | * threaded model) but re-evaluate this once memcpy_flushcache() is | |
1185 | * enabled to use movdir64b which might invalidate this performance | |
1186 | * advantage seen with cache-allocating-writes plus flushing. | |
1187 | */ | |
1188 | #ifdef CONFIG_X86 | |
1189 | if (static_cpu_has(X86_FEATURE_CLFLUSHOPT) && | |
1190 | likely(boot_cpu_data.x86_clflush_size == 64) && | |
1191 | likely(size >= 768)) { | |
1192 | do { | |
1193 | memcpy((void *)dest, (void *)source, 64); | |
1194 | clflushopt((void *)dest); | |
1195 | dest += 64; | |
1196 | source += 64; | |
1197 | size -= 64; | |
1198 | } while (size >= 64); | |
1199 | return; | |
1200 | } | |
1201 | #endif | |
1202 | memcpy_flushcache(dest, source, size); | |
1203 | } | |
1204 | ||
48debafe MP |
1205 | static void bio_copy_block(struct dm_writecache *wc, struct bio *bio, void *data) |
1206 | { | |
1207 | void *buf; | |
1208 | unsigned long flags; | |
1209 | unsigned size; | |
1210 | int rw = bio_data_dir(bio); | |
1211 | unsigned remaining_size = wc->block_size; | |
1212 | ||
1213 | do { | |
1214 | struct bio_vec bv = bio_iter_iovec(bio, bio->bi_iter); | |
1215 | buf = bvec_kmap_irq(&bv, &flags); | |
1216 | size = bv.bv_len; | |
1217 | if (unlikely(size > remaining_size)) | |
1218 | size = remaining_size; | |
1219 | ||
1220 | if (rw == READ) { | |
1221 | int r; | |
ec6347bb | 1222 | r = copy_mc_to_kernel(buf, data, size); |
48debafe MP |
1223 | flush_dcache_page(bio_page(bio)); |
1224 | if (unlikely(r)) { | |
1225 | writecache_error(wc, r, "hardware memory error when reading data: %d", r); | |
1226 | bio->bi_status = BLK_STS_IOERR; | |
1227 | } | |
1228 | } else { | |
1229 | flush_dcache_page(bio_page(bio)); | |
48338daa | 1230 | memcpy_flushcache_optimized(data, buf, size); |
48debafe MP |
1231 | } |
1232 | ||
1233 | bvec_kunmap_irq(buf, &flags); | |
1234 | ||
1235 | data = (char *)data + size; | |
1236 | remaining_size -= size; | |
1237 | bio_advance(bio, size); | |
1238 | } while (unlikely(remaining_size)); | |
1239 | } | |
1240 | ||
1241 | static int writecache_flush_thread(void *data) | |
1242 | { | |
1243 | struct dm_writecache *wc = data; | |
1244 | ||
1245 | while (1) { | |
1246 | struct bio *bio; | |
1247 | ||
1248 | wc_lock(wc); | |
1249 | bio = bio_list_pop(&wc->flush_list); | |
1250 | if (!bio) { | |
1251 | set_current_state(TASK_INTERRUPTIBLE); | |
1252 | wc_unlock(wc); | |
1253 | ||
1254 | if (unlikely(kthread_should_stop())) { | |
1255 | set_current_state(TASK_RUNNING); | |
1256 | break; | |
1257 | } | |
1258 | ||
1259 | schedule(); | |
1260 | continue; | |
1261 | } | |
1262 | ||
1263 | if (bio_op(bio) == REQ_OP_DISCARD) { | |
1264 | writecache_discard(wc, bio->bi_iter.bi_sector, | |
1265 | bio_end_sector(bio)); | |
1266 | wc_unlock(wc); | |
1267 | bio_set_dev(bio, wc->dev->bdev); | |
ed00aabd | 1268 | submit_bio_noacct(bio); |
48debafe MP |
1269 | } else { |
1270 | writecache_flush(wc); | |
1271 | wc_unlock(wc); | |
1272 | if (writecache_has_error(wc)) | |
1273 | bio->bi_status = BLK_STS_IOERR; | |
1274 | bio_endio(bio); | |
1275 | } | |
1276 | } | |
1277 | ||
1278 | return 0; | |
1279 | } | |
1280 | ||
1281 | static void writecache_offload_bio(struct dm_writecache *wc, struct bio *bio) | |
1282 | { | |
1283 | if (bio_list_empty(&wc->flush_list)) | |
1284 | wake_up_process(wc->flush_thread); | |
1285 | bio_list_add(&wc->flush_list, bio); | |
1286 | } | |
1287 | ||
1288 | static int writecache_map(struct dm_target *ti, struct bio *bio) | |
1289 | { | |
1290 | struct wc_entry *e; | |
1291 | struct dm_writecache *wc = ti->private; | |
1292 | ||
1293 | bio->bi_private = NULL; | |
1294 | ||
1295 | wc_lock(wc); | |
1296 | ||
1297 | if (unlikely(bio->bi_opf & REQ_PREFLUSH)) { | |
1298 | if (writecache_has_error(wc)) | |
1299 | goto unlock_error; | |
1300 | if (WC_MODE_PMEM(wc)) { | |
1301 | writecache_flush(wc); | |
1302 | if (writecache_has_error(wc)) | |
1303 | goto unlock_error; | |
1304 | goto unlock_submit; | |
1305 | } else { | |
1306 | writecache_offload_bio(wc, bio); | |
1307 | goto unlock_return; | |
1308 | } | |
1309 | } | |
1310 | ||
1311 | bio->bi_iter.bi_sector = dm_target_offset(ti, bio->bi_iter.bi_sector); | |
1312 | ||
1313 | if (unlikely((((unsigned)bio->bi_iter.bi_sector | bio_sectors(bio)) & | |
1314 | (wc->block_size / 512 - 1)) != 0)) { | |
1315 | DMERR("I/O is not aligned, sector %llu, size %u, block size %u", | |
1316 | (unsigned long long)bio->bi_iter.bi_sector, | |
1317 | bio->bi_iter.bi_size, wc->block_size); | |
1318 | goto unlock_error; | |
1319 | } | |
1320 | ||
1321 | if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) { | |
1322 | if (writecache_has_error(wc)) | |
1323 | goto unlock_error; | |
1324 | if (WC_MODE_PMEM(wc)) { | |
1325 | writecache_discard(wc, bio->bi_iter.bi_sector, bio_end_sector(bio)); | |
1326 | goto unlock_remap_origin; | |
1327 | } else { | |
1328 | writecache_offload_bio(wc, bio); | |
1329 | goto unlock_return; | |
1330 | } | |
1331 | } | |
1332 | ||
1333 | if (bio_data_dir(bio) == READ) { | |
1334 | read_next_block: | |
1335 | e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING); | |
1336 | if (e && read_original_sector(wc, e) == bio->bi_iter.bi_sector) { | |
1337 | if (WC_MODE_PMEM(wc)) { | |
1338 | bio_copy_block(wc, bio, memory_data(wc, e)); | |
1339 | if (bio->bi_iter.bi_size) | |
1340 | goto read_next_block; | |
1341 | goto unlock_submit; | |
1342 | } else { | |
1343 | dm_accept_partial_bio(bio, wc->block_size >> SECTOR_SHIFT); | |
1344 | bio_set_dev(bio, wc->ssd_dev->bdev); | |
1345 | bio->bi_iter.bi_sector = cache_sector(wc, e); | |
1346 | if (!writecache_entry_is_committed(wc, e)) | |
1347 | writecache_wait_for_ios(wc, WRITE); | |
1348 | goto unlock_remap; | |
1349 | } | |
1350 | } else { | |
1351 | if (e) { | |
1352 | sector_t next_boundary = | |
1353 | read_original_sector(wc, e) - bio->bi_iter.bi_sector; | |
1354 | if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) { | |
1355 | dm_accept_partial_bio(bio, next_boundary); | |
1356 | } | |
1357 | } | |
1358 | goto unlock_remap_origin; | |
1359 | } | |
1360 | } else { | |
1361 | do { | |
d53f1faf | 1362 | bool found_entry = false; |
48debafe MP |
1363 | if (writecache_has_error(wc)) |
1364 | goto unlock_error; | |
1365 | e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0); | |
1366 | if (e) { | |
1367 | if (!writecache_entry_is_committed(wc, e)) | |
1368 | goto bio_copy; | |
1369 | if (!WC_MODE_PMEM(wc) && !e->write_in_progress) { | |
1370 | wc->overwrote_committed = true; | |
1371 | goto bio_copy; | |
1372 | } | |
d53f1faf | 1373 | found_entry = true; |
93de44eb MP |
1374 | } else { |
1375 | if (unlikely(wc->cleaner)) | |
1376 | goto direct_write; | |
48debafe | 1377 | } |
dcd19507 | 1378 | e = writecache_pop_from_freelist(wc, (sector_t)-1); |
48debafe | 1379 | if (unlikely(!e)) { |
d53f1faf | 1380 | if (!found_entry) { |
93de44eb | 1381 | direct_write: |
d53f1faf MP |
1382 | e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING); |
1383 | if (e) { | |
1384 | sector_t next_boundary = read_original_sector(wc, e) - bio->bi_iter.bi_sector; | |
1385 | BUG_ON(!next_boundary); | |
1386 | if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) { | |
1387 | dm_accept_partial_bio(bio, next_boundary); | |
1388 | } | |
1389 | } | |
1390 | goto unlock_remap_origin; | |
1391 | } | |
48debafe MP |
1392 | writecache_wait_on_freelist(wc); |
1393 | continue; | |
1394 | } | |
1395 | write_original_sector_seq_count(wc, e, bio->bi_iter.bi_sector, wc->seq_count); | |
1396 | writecache_insert_entry(wc, e); | |
1397 | wc->uncommitted_blocks++; | |
1398 | bio_copy: | |
1399 | if (WC_MODE_PMEM(wc)) { | |
1400 | bio_copy_block(wc, bio, memory_data(wc, e)); | |
1401 | } else { | |
dcd19507 MP |
1402 | unsigned bio_size = wc->block_size; |
1403 | sector_t start_cache_sec = cache_sector(wc, e); | |
1404 | sector_t current_cache_sec = start_cache_sec + (bio_size >> SECTOR_SHIFT); | |
1405 | ||
1406 | while (bio_size < bio->bi_iter.bi_size) { | |
1407 | struct wc_entry *f = writecache_pop_from_freelist(wc, current_cache_sec); | |
1408 | if (!f) | |
1409 | break; | |
1410 | write_original_sector_seq_count(wc, f, bio->bi_iter.bi_sector + | |
1411 | (bio_size >> SECTOR_SHIFT), wc->seq_count); | |
1412 | writecache_insert_entry(wc, f); | |
1413 | wc->uncommitted_blocks++; | |
1414 | bio_size += wc->block_size; | |
1415 | current_cache_sec += wc->block_size >> SECTOR_SHIFT; | |
1416 | } | |
1417 | ||
48debafe | 1418 | bio_set_dev(bio, wc->ssd_dev->bdev); |
dcd19507 MP |
1419 | bio->bi_iter.bi_sector = start_cache_sec; |
1420 | dm_accept_partial_bio(bio, bio_size >> SECTOR_SHIFT); | |
1421 | ||
48debafe MP |
1422 | if (unlikely(wc->uncommitted_blocks >= wc->autocommit_blocks)) { |
1423 | wc->uncommitted_blocks = 0; | |
1424 | queue_work(wc->writeback_wq, &wc->flush_work); | |
1425 | } else { | |
1426 | writecache_schedule_autocommit(wc); | |
1427 | } | |
1428 | goto unlock_remap; | |
1429 | } | |
1430 | } while (bio->bi_iter.bi_size); | |
1431 | ||
c1005322 MM |
1432 | if (unlikely(bio->bi_opf & REQ_FUA || |
1433 | wc->uncommitted_blocks >= wc->autocommit_blocks)) | |
48debafe MP |
1434 | writecache_flush(wc); |
1435 | else | |
1436 | writecache_schedule_autocommit(wc); | |
1437 | goto unlock_submit; | |
1438 | } | |
1439 | ||
1440 | unlock_remap_origin: | |
1441 | bio_set_dev(bio, wc->dev->bdev); | |
1442 | wc_unlock(wc); | |
1443 | return DM_MAPIO_REMAPPED; | |
1444 | ||
1445 | unlock_remap: | |
1446 | /* make sure that writecache_end_io decrements bio_in_progress: */ | |
1447 | bio->bi_private = (void *)1; | |
1448 | atomic_inc(&wc->bio_in_progress[bio_data_dir(bio)]); | |
1449 | wc_unlock(wc); | |
1450 | return DM_MAPIO_REMAPPED; | |
1451 | ||
1452 | unlock_submit: | |
1453 | wc_unlock(wc); | |
1454 | bio_endio(bio); | |
1455 | return DM_MAPIO_SUBMITTED; | |
1456 | ||
1457 | unlock_return: | |
1458 | wc_unlock(wc); | |
1459 | return DM_MAPIO_SUBMITTED; | |
1460 | ||
1461 | unlock_error: | |
1462 | wc_unlock(wc); | |
1463 | bio_io_error(bio); | |
1464 | return DM_MAPIO_SUBMITTED; | |
1465 | } | |
1466 | ||
1467 | static int writecache_end_io(struct dm_target *ti, struct bio *bio, blk_status_t *status) | |
1468 | { | |
1469 | struct dm_writecache *wc = ti->private; | |
1470 | ||
1471 | if (bio->bi_private != NULL) { | |
1472 | int dir = bio_data_dir(bio); | |
1473 | if (atomic_dec_and_test(&wc->bio_in_progress[dir])) | |
1474 | if (unlikely(waitqueue_active(&wc->bio_in_progress_wait[dir]))) | |
1475 | wake_up(&wc->bio_in_progress_wait[dir]); | |
1476 | } | |
1477 | return 0; | |
1478 | } | |
1479 | ||
1480 | static int writecache_iterate_devices(struct dm_target *ti, | |
1481 | iterate_devices_callout_fn fn, void *data) | |
1482 | { | |
1483 | struct dm_writecache *wc = ti->private; | |
1484 | ||
1485 | return fn(ti, wc->dev, 0, ti->len, data); | |
1486 | } | |
1487 | ||
1488 | static void writecache_io_hints(struct dm_target *ti, struct queue_limits *limits) | |
1489 | { | |
1490 | struct dm_writecache *wc = ti->private; | |
1491 | ||
1492 | if (limits->logical_block_size < wc->block_size) | |
1493 | limits->logical_block_size = wc->block_size; | |
1494 | ||
1495 | if (limits->physical_block_size < wc->block_size) | |
1496 | limits->physical_block_size = wc->block_size; | |
1497 | ||
1498 | if (limits->io_min < wc->block_size) | |
1499 | limits->io_min = wc->block_size; | |
1500 | } | |
1501 | ||
1502 | ||
1503 | static void writecache_writeback_endio(struct bio *bio) | |
1504 | { | |
1505 | struct writeback_struct *wb = container_of(bio, struct writeback_struct, bio); | |
1506 | struct dm_writecache *wc = wb->wc; | |
1507 | unsigned long flags; | |
1508 | ||
1509 | raw_spin_lock_irqsave(&wc->endio_list_lock, flags); | |
1510 | if (unlikely(list_empty(&wc->endio_list))) | |
1511 | wake_up_process(wc->endio_thread); | |
1512 | list_add_tail(&wb->endio_entry, &wc->endio_list); | |
1513 | raw_spin_unlock_irqrestore(&wc->endio_list_lock, flags); | |
1514 | } | |
1515 | ||
1516 | static void writecache_copy_endio(int read_err, unsigned long write_err, void *ptr) | |
1517 | { | |
1518 | struct copy_struct *c = ptr; | |
1519 | struct dm_writecache *wc = c->wc; | |
1520 | ||
1521 | c->error = likely(!(read_err | write_err)) ? 0 : -EIO; | |
1522 | ||
1523 | raw_spin_lock_irq(&wc->endio_list_lock); | |
1524 | if (unlikely(list_empty(&wc->endio_list))) | |
1525 | wake_up_process(wc->endio_thread); | |
1526 | list_add_tail(&c->endio_entry, &wc->endio_list); | |
1527 | raw_spin_unlock_irq(&wc->endio_list_lock); | |
1528 | } | |
1529 | ||
1530 | static void __writecache_endio_pmem(struct dm_writecache *wc, struct list_head *list) | |
1531 | { | |
1532 | unsigned i; | |
1533 | struct writeback_struct *wb; | |
1534 | struct wc_entry *e; | |
1535 | unsigned long n_walked = 0; | |
1536 | ||
1537 | do { | |
1538 | wb = list_entry(list->next, struct writeback_struct, endio_entry); | |
1539 | list_del(&wb->endio_entry); | |
1540 | ||
1541 | if (unlikely(wb->bio.bi_status != BLK_STS_OK)) | |
1542 | writecache_error(wc, blk_status_to_errno(wb->bio.bi_status), | |
1543 | "write error %d", wb->bio.bi_status); | |
1544 | i = 0; | |
1545 | do { | |
1546 | e = wb->wc_list[i]; | |
1547 | BUG_ON(!e->write_in_progress); | |
1548 | e->write_in_progress = false; | |
1549 | INIT_LIST_HEAD(&e->lru); | |
1550 | if (!writecache_has_error(wc)) | |
1551 | writecache_free_entry(wc, e); | |
1552 | BUG_ON(!wc->writeback_size); | |
1553 | wc->writeback_size--; | |
1554 | n_walked++; | |
1555 | if (unlikely(n_walked >= ENDIO_LATENCY)) { | |
aa950920 | 1556 | writecache_commit_flushed(wc, false); |
48debafe MP |
1557 | wc_unlock(wc); |
1558 | wc_lock(wc); | |
1559 | n_walked = 0; | |
1560 | } | |
1561 | } while (++i < wb->wc_list_n); | |
1562 | ||
1563 | if (wb->wc_list != wb->wc_list_inline) | |
1564 | kfree(wb->wc_list); | |
1565 | bio_put(&wb->bio); | |
1566 | } while (!list_empty(list)); | |
1567 | } | |
1568 | ||
1569 | static void __writecache_endio_ssd(struct dm_writecache *wc, struct list_head *list) | |
1570 | { | |
1571 | struct copy_struct *c; | |
1572 | struct wc_entry *e; | |
1573 | ||
1574 | do { | |
1575 | c = list_entry(list->next, struct copy_struct, endio_entry); | |
1576 | list_del(&c->endio_entry); | |
1577 | ||
1578 | if (unlikely(c->error)) | |
1579 | writecache_error(wc, c->error, "copy error"); | |
1580 | ||
1581 | e = c->e; | |
1582 | do { | |
1583 | BUG_ON(!e->write_in_progress); | |
1584 | e->write_in_progress = false; | |
1585 | INIT_LIST_HEAD(&e->lru); | |
1586 | if (!writecache_has_error(wc)) | |
1587 | writecache_free_entry(wc, e); | |
1588 | ||
1589 | BUG_ON(!wc->writeback_size); | |
1590 | wc->writeback_size--; | |
1591 | e++; | |
1592 | } while (--c->n_entries); | |
1593 | mempool_free(c, &wc->copy_pool); | |
1594 | } while (!list_empty(list)); | |
1595 | } | |
1596 | ||
1597 | static int writecache_endio_thread(void *data) | |
1598 | { | |
1599 | struct dm_writecache *wc = data; | |
1600 | ||
1601 | while (1) { | |
1602 | struct list_head list; | |
1603 | ||
1604 | raw_spin_lock_irq(&wc->endio_list_lock); | |
1605 | if (!list_empty(&wc->endio_list)) | |
1606 | goto pop_from_list; | |
1607 | set_current_state(TASK_INTERRUPTIBLE); | |
1608 | raw_spin_unlock_irq(&wc->endio_list_lock); | |
1609 | ||
1610 | if (unlikely(kthread_should_stop())) { | |
1611 | set_current_state(TASK_RUNNING); | |
1612 | break; | |
1613 | } | |
1614 | ||
1615 | schedule(); | |
1616 | ||
1617 | continue; | |
1618 | ||
1619 | pop_from_list: | |
1620 | list = wc->endio_list; | |
1621 | list.next->prev = list.prev->next = &list; | |
1622 | INIT_LIST_HEAD(&wc->endio_list); | |
1623 | raw_spin_unlock_irq(&wc->endio_list_lock); | |
1624 | ||
1625 | if (!WC_MODE_FUA(wc)) | |
1626 | writecache_disk_flush(wc, wc->dev); | |
1627 | ||
1628 | wc_lock(wc); | |
1629 | ||
1630 | if (WC_MODE_PMEM(wc)) { | |
1631 | __writecache_endio_pmem(wc, &list); | |
1632 | } else { | |
1633 | __writecache_endio_ssd(wc, &list); | |
1634 | writecache_wait_for_ios(wc, READ); | |
1635 | } | |
1636 | ||
aa950920 | 1637 | writecache_commit_flushed(wc, false); |
48debafe MP |
1638 | |
1639 | wc_unlock(wc); | |
1640 | } | |
1641 | ||
1642 | return 0; | |
1643 | } | |
1644 | ||
1645 | static bool wc_add_block(struct writeback_struct *wb, struct wc_entry *e, gfp_t gfp) | |
1646 | { | |
1647 | struct dm_writecache *wc = wb->wc; | |
1648 | unsigned block_size = wc->block_size; | |
1649 | void *address = memory_data(wc, e); | |
1650 | ||
1651 | persistent_memory_flush_cache(address, block_size); | |
4134455f MP |
1652 | |
1653 | if (unlikely(bio_end_sector(&wb->bio) >= wc->data_device_sectors)) | |
1654 | return true; | |
1655 | ||
48debafe MP |
1656 | return bio_add_page(&wb->bio, persistent_memory_page(address), |
1657 | block_size, persistent_memory_page_offset(address)) != 0; | |
1658 | } | |
1659 | ||
1660 | struct writeback_list { | |
1661 | struct list_head list; | |
1662 | size_t size; | |
1663 | }; | |
1664 | ||
1665 | static void __writeback_throttle(struct dm_writecache *wc, struct writeback_list *wbl) | |
1666 | { | |
1667 | if (unlikely(wc->max_writeback_jobs)) { | |
1668 | if (READ_ONCE(wc->writeback_size) - wbl->size >= wc->max_writeback_jobs) { | |
1669 | wc_lock(wc); | |
1670 | while (wc->writeback_size - wbl->size >= wc->max_writeback_jobs) | |
1671 | writecache_wait_on_freelist(wc); | |
1672 | wc_unlock(wc); | |
1673 | } | |
1674 | } | |
1675 | cond_resched(); | |
1676 | } | |
1677 | ||
1678 | static void __writecache_writeback_pmem(struct dm_writecache *wc, struct writeback_list *wbl) | |
1679 | { | |
1680 | struct wc_entry *e, *f; | |
1681 | struct bio *bio; | |
1682 | struct writeback_struct *wb; | |
1683 | unsigned max_pages; | |
1684 | ||
1685 | while (wbl->size) { | |
1686 | wbl->size--; | |
1687 | e = container_of(wbl->list.prev, struct wc_entry, lru); | |
1688 | list_del(&e->lru); | |
1689 | ||
1690 | max_pages = e->wc_list_contiguous; | |
1691 | ||
1692 | bio = bio_alloc_bioset(GFP_NOIO, max_pages, &wc->bio_set); | |
1693 | wb = container_of(bio, struct writeback_struct, bio); | |
1694 | wb->wc = wc; | |
09f2d656 HY |
1695 | bio->bi_end_io = writecache_writeback_endio; |
1696 | bio_set_dev(bio, wc->dev->bdev); | |
1697 | bio->bi_iter.bi_sector = read_original_sector(wc, e); | |
48debafe | 1698 | if (max_pages <= WB_LIST_INLINE || |
50a7d3ba KC |
1699 | unlikely(!(wb->wc_list = kmalloc_array(max_pages, sizeof(struct wc_entry *), |
1700 | GFP_NOIO | __GFP_NORETRY | | |
1701 | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { | |
48debafe MP |
1702 | wb->wc_list = wb->wc_list_inline; |
1703 | max_pages = WB_LIST_INLINE; | |
1704 | } | |
1705 | ||
1706 | BUG_ON(!wc_add_block(wb, e, GFP_NOIO)); | |
1707 | ||
1708 | wb->wc_list[0] = e; | |
1709 | wb->wc_list_n = 1; | |
1710 | ||
1711 | while (wbl->size && wb->wc_list_n < max_pages) { | |
1712 | f = container_of(wbl->list.prev, struct wc_entry, lru); | |
1713 | if (read_original_sector(wc, f) != | |
1714 | read_original_sector(wc, e) + (wc->block_size >> SECTOR_SHIFT)) | |
1715 | break; | |
1716 | if (!wc_add_block(wb, f, GFP_NOWAIT | __GFP_NOWARN)) | |
1717 | break; | |
1718 | wbl->size--; | |
1719 | list_del(&f->lru); | |
1720 | wb->wc_list[wb->wc_list_n++] = f; | |
1721 | e = f; | |
1722 | } | |
09f2d656 | 1723 | bio_set_op_attrs(bio, REQ_OP_WRITE, WC_MODE_FUA(wc) * REQ_FUA); |
48debafe MP |
1724 | if (writecache_has_error(wc)) { |
1725 | bio->bi_status = BLK_STS_IOERR; | |
09f2d656 | 1726 | bio_endio(bio); |
4134455f MP |
1727 | } else if (unlikely(!bio_sectors(bio))) { |
1728 | bio->bi_status = BLK_STS_OK; | |
1729 | bio_endio(bio); | |
48debafe | 1730 | } else { |
09f2d656 | 1731 | submit_bio(bio); |
48debafe MP |
1732 | } |
1733 | ||
1734 | __writeback_throttle(wc, wbl); | |
1735 | } | |
1736 | } | |
1737 | ||
1738 | static void __writecache_writeback_ssd(struct dm_writecache *wc, struct writeback_list *wbl) | |
1739 | { | |
1740 | struct wc_entry *e, *f; | |
1741 | struct dm_io_region from, to; | |
1742 | struct copy_struct *c; | |
1743 | ||
1744 | while (wbl->size) { | |
1745 | unsigned n_sectors; | |
1746 | ||
1747 | wbl->size--; | |
1748 | e = container_of(wbl->list.prev, struct wc_entry, lru); | |
1749 | list_del(&e->lru); | |
1750 | ||
1751 | n_sectors = e->wc_list_contiguous << (wc->block_size_bits - SECTOR_SHIFT); | |
1752 | ||
1753 | from.bdev = wc->ssd_dev->bdev; | |
1754 | from.sector = cache_sector(wc, e); | |
1755 | from.count = n_sectors; | |
1756 | to.bdev = wc->dev->bdev; | |
1757 | to.sector = read_original_sector(wc, e); | |
1758 | to.count = n_sectors; | |
1759 | ||
1760 | c = mempool_alloc(&wc->copy_pool, GFP_NOIO); | |
1761 | c->wc = wc; | |
1762 | c->e = e; | |
1763 | c->n_entries = e->wc_list_contiguous; | |
1764 | ||
1765 | while ((n_sectors -= wc->block_size >> SECTOR_SHIFT)) { | |
1766 | wbl->size--; | |
1767 | f = container_of(wbl->list.prev, struct wc_entry, lru); | |
1768 | BUG_ON(f != e + 1); | |
1769 | list_del(&f->lru); | |
1770 | e = f; | |
1771 | } | |
1772 | ||
4134455f MP |
1773 | if (unlikely(to.sector + to.count > wc->data_device_sectors)) { |
1774 | if (to.sector >= wc->data_device_sectors) { | |
1775 | writecache_copy_endio(0, 0, c); | |
1776 | continue; | |
1777 | } | |
1778 | from.count = to.count = wc->data_device_sectors - to.sector; | |
1779 | } | |
1780 | ||
48debafe MP |
1781 | dm_kcopyd_copy(wc->dm_kcopyd, &from, 1, &to, 0, writecache_copy_endio, c); |
1782 | ||
1783 | __writeback_throttle(wc, wbl); | |
1784 | } | |
1785 | } | |
1786 | ||
1787 | static void writecache_writeback(struct work_struct *work) | |
1788 | { | |
1789 | struct dm_writecache *wc = container_of(work, struct dm_writecache, writeback_work); | |
1790 | struct blk_plug plug; | |
3f649ab7 | 1791 | struct wc_entry *f, *g, *e = NULL; |
48debafe MP |
1792 | struct rb_node *node, *next_node; |
1793 | struct list_head skipped; | |
1794 | struct writeback_list wbl; | |
1795 | unsigned long n_walked; | |
1796 | ||
1797 | wc_lock(wc); | |
1798 | restart: | |
1799 | if (writecache_has_error(wc)) { | |
1800 | wc_unlock(wc); | |
1801 | return; | |
1802 | } | |
1803 | ||
1804 | if (unlikely(wc->writeback_all)) { | |
1805 | if (writecache_wait_for_writeback(wc)) | |
1806 | goto restart; | |
1807 | } | |
1808 | ||
1809 | if (wc->overwrote_committed) { | |
1810 | writecache_wait_for_ios(wc, WRITE); | |
1811 | } | |
1812 | ||
1813 | n_walked = 0; | |
1814 | INIT_LIST_HEAD(&skipped); | |
1815 | INIT_LIST_HEAD(&wbl.list); | |
1816 | wbl.size = 0; | |
1817 | while (!list_empty(&wc->lru) && | |
1818 | (wc->writeback_all || | |
3923d485 MP |
1819 | wc->freelist_size + wc->writeback_size <= wc->freelist_low_watermark || |
1820 | (jiffies - container_of(wc->lru.prev, struct wc_entry, lru)->age >= | |
1821 | wc->max_age - wc->max_age / MAX_AGE_DIV))) { | |
48debafe MP |
1822 | |
1823 | n_walked++; | |
1824 | if (unlikely(n_walked > WRITEBACK_LATENCY) && | |
1825 | likely(!wc->writeback_all) && likely(!dm_suspended(wc->ti))) { | |
1826 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
1827 | break; | |
1828 | } | |
1829 | ||
5229b489 HY |
1830 | if (unlikely(wc->writeback_all)) { |
1831 | if (unlikely(!e)) { | |
1832 | writecache_flush(wc); | |
1833 | e = container_of(rb_first(&wc->tree), struct wc_entry, rb_node); | |
1834 | } else | |
1835 | e = g; | |
1836 | } else | |
1837 | e = container_of(wc->lru.prev, struct wc_entry, lru); | |
48debafe MP |
1838 | BUG_ON(e->write_in_progress); |
1839 | if (unlikely(!writecache_entry_is_committed(wc, e))) { | |
1840 | writecache_flush(wc); | |
1841 | } | |
1842 | node = rb_prev(&e->rb_node); | |
1843 | if (node) { | |
1844 | f = container_of(node, struct wc_entry, rb_node); | |
1845 | if (unlikely(read_original_sector(wc, f) == | |
1846 | read_original_sector(wc, e))) { | |
1847 | BUG_ON(!f->write_in_progress); | |
1848 | list_del(&e->lru); | |
1849 | list_add(&e->lru, &skipped); | |
1850 | cond_resched(); | |
1851 | continue; | |
1852 | } | |
1853 | } | |
1854 | wc->writeback_size++; | |
1855 | list_del(&e->lru); | |
1856 | list_add(&e->lru, &wbl.list); | |
1857 | wbl.size++; | |
1858 | e->write_in_progress = true; | |
1859 | e->wc_list_contiguous = 1; | |
1860 | ||
1861 | f = e; | |
1862 | ||
1863 | while (1) { | |
1864 | next_node = rb_next(&f->rb_node); | |
1865 | if (unlikely(!next_node)) | |
1866 | break; | |
1867 | g = container_of(next_node, struct wc_entry, rb_node); | |
62421b38 HY |
1868 | if (unlikely(read_original_sector(wc, g) == |
1869 | read_original_sector(wc, f))) { | |
48debafe MP |
1870 | f = g; |
1871 | continue; | |
1872 | } | |
1873 | if (read_original_sector(wc, g) != | |
1874 | read_original_sector(wc, f) + (wc->block_size >> SECTOR_SHIFT)) | |
1875 | break; | |
1876 | if (unlikely(g->write_in_progress)) | |
1877 | break; | |
1878 | if (unlikely(!writecache_entry_is_committed(wc, g))) | |
1879 | break; | |
1880 | ||
1881 | if (!WC_MODE_PMEM(wc)) { | |
1882 | if (g != f + 1) | |
1883 | break; | |
1884 | } | |
1885 | ||
1886 | n_walked++; | |
1887 | //if (unlikely(n_walked > WRITEBACK_LATENCY) && likely(!wc->writeback_all)) | |
1888 | // break; | |
1889 | ||
1890 | wc->writeback_size++; | |
1891 | list_del(&g->lru); | |
1892 | list_add(&g->lru, &wbl.list); | |
1893 | wbl.size++; | |
1894 | g->write_in_progress = true; | |
a8affc03 | 1895 | g->wc_list_contiguous = BIO_MAX_VECS; |
48debafe MP |
1896 | f = g; |
1897 | e->wc_list_contiguous++; | |
a8affc03 | 1898 | if (unlikely(e->wc_list_contiguous == BIO_MAX_VECS)) { |
5229b489 HY |
1899 | if (unlikely(wc->writeback_all)) { |
1900 | next_node = rb_next(&f->rb_node); | |
1901 | if (likely(next_node)) | |
1902 | g = container_of(next_node, struct wc_entry, rb_node); | |
1903 | } | |
48debafe | 1904 | break; |
5229b489 | 1905 | } |
48debafe MP |
1906 | } |
1907 | cond_resched(); | |
1908 | } | |
1909 | ||
1910 | if (!list_empty(&skipped)) { | |
1911 | list_splice_tail(&skipped, &wc->lru); | |
1912 | /* | |
1913 | * If we didn't do any progress, we must wait until some | |
1914 | * writeback finishes to avoid burning CPU in a loop | |
1915 | */ | |
1916 | if (unlikely(!wbl.size)) | |
1917 | writecache_wait_for_writeback(wc); | |
1918 | } | |
1919 | ||
1920 | wc_unlock(wc); | |
1921 | ||
1922 | blk_start_plug(&plug); | |
1923 | ||
1924 | if (WC_MODE_PMEM(wc)) | |
1925 | __writecache_writeback_pmem(wc, &wbl); | |
1926 | else | |
1927 | __writecache_writeback_ssd(wc, &wbl); | |
1928 | ||
1929 | blk_finish_plug(&plug); | |
1930 | ||
1931 | if (unlikely(wc->writeback_all)) { | |
1932 | wc_lock(wc); | |
1933 | while (writecache_wait_for_writeback(wc)); | |
1934 | wc_unlock(wc); | |
1935 | } | |
1936 | } | |
1937 | ||
1938 | static int calculate_memory_size(uint64_t device_size, unsigned block_size, | |
1939 | size_t *n_blocks_p, size_t *n_metadata_blocks_p) | |
1940 | { | |
1941 | uint64_t n_blocks, offset; | |
1942 | struct wc_entry e; | |
1943 | ||
1944 | n_blocks = device_size; | |
1945 | do_div(n_blocks, block_size + sizeof(struct wc_memory_entry)); | |
1946 | ||
1947 | while (1) { | |
1948 | if (!n_blocks) | |
1949 | return -ENOSPC; | |
1950 | /* Verify the following entries[n_blocks] won't overflow */ | |
1951 | if (n_blocks >= ((size_t)-sizeof(struct wc_memory_superblock) / | |
1952 | sizeof(struct wc_memory_entry))) | |
1953 | return -EFBIG; | |
1954 | offset = offsetof(struct wc_memory_superblock, entries[n_blocks]); | |
1955 | offset = (offset + block_size - 1) & ~(uint64_t)(block_size - 1); | |
1956 | if (offset + n_blocks * block_size <= device_size) | |
1957 | break; | |
1958 | n_blocks--; | |
1959 | } | |
1960 | ||
1961 | /* check if the bit field overflows */ | |
1962 | e.index = n_blocks; | |
1963 | if (e.index != n_blocks) | |
1964 | return -EFBIG; | |
1965 | ||
1966 | if (n_blocks_p) | |
1967 | *n_blocks_p = n_blocks; | |
1968 | if (n_metadata_blocks_p) | |
1969 | *n_metadata_blocks_p = offset >> __ffs(block_size); | |
1970 | return 0; | |
1971 | } | |
1972 | ||
1973 | static int init_memory(struct dm_writecache *wc) | |
1974 | { | |
1975 | size_t b; | |
1976 | int r; | |
1977 | ||
1978 | r = calculate_memory_size(wc->memory_map_size, wc->block_size, &wc->n_blocks, NULL); | |
1979 | if (r) | |
1980 | return r; | |
1981 | ||
1982 | r = writecache_alloc_entries(wc); | |
1983 | if (r) | |
1984 | return r; | |
1985 | ||
1986 | for (b = 0; b < ARRAY_SIZE(sb(wc)->padding); b++) | |
1987 | pmem_assign(sb(wc)->padding[b], cpu_to_le64(0)); | |
1988 | pmem_assign(sb(wc)->version, cpu_to_le32(MEMORY_SUPERBLOCK_VERSION)); | |
1989 | pmem_assign(sb(wc)->block_size, cpu_to_le32(wc->block_size)); | |
1990 | pmem_assign(sb(wc)->n_blocks, cpu_to_le64(wc->n_blocks)); | |
1991 | pmem_assign(sb(wc)->seq_count, cpu_to_le64(0)); | |
1992 | ||
1edaa447 | 1993 | for (b = 0; b < wc->n_blocks; b++) { |
48debafe | 1994 | write_original_sector_seq_count(wc, &wc->entries[b], -1, -1); |
1edaa447 MP |
1995 | cond_resched(); |
1996 | } | |
48debafe MP |
1997 | |
1998 | writecache_flush_all_metadata(wc); | |
aa950920 | 1999 | writecache_commit_flushed(wc, false); |
48debafe MP |
2000 | pmem_assign(sb(wc)->magic, cpu_to_le32(MEMORY_SUPERBLOCK_MAGIC)); |
2001 | writecache_flush_region(wc, &sb(wc)->magic, sizeof sb(wc)->magic); | |
aa950920 | 2002 | writecache_commit_flushed(wc, false); |
48debafe MP |
2003 | |
2004 | return 0; | |
2005 | } | |
2006 | ||
2007 | static void writecache_dtr(struct dm_target *ti) | |
2008 | { | |
2009 | struct dm_writecache *wc = ti->private; | |
2010 | ||
2011 | if (!wc) | |
2012 | return; | |
2013 | ||
2014 | if (wc->endio_thread) | |
2015 | kthread_stop(wc->endio_thread); | |
2016 | ||
2017 | if (wc->flush_thread) | |
2018 | kthread_stop(wc->flush_thread); | |
2019 | ||
2020 | bioset_exit(&wc->bio_set); | |
2021 | ||
2022 | mempool_exit(&wc->copy_pool); | |
2023 | ||
2024 | if (wc->writeback_wq) | |
2025 | destroy_workqueue(wc->writeback_wq); | |
2026 | ||
2027 | if (wc->dev) | |
2028 | dm_put_device(ti, wc->dev); | |
2029 | ||
2030 | if (wc->ssd_dev) | |
2031 | dm_put_device(ti, wc->ssd_dev); | |
2032 | ||
21ec672e | 2033 | vfree(wc->entries); |
48debafe MP |
2034 | |
2035 | if (wc->memory_map) { | |
2036 | if (WC_MODE_PMEM(wc)) | |
2037 | persistent_memory_release(wc); | |
2038 | else | |
2039 | vfree(wc->memory_map); | |
2040 | } | |
2041 | ||
2042 | if (wc->dm_kcopyd) | |
2043 | dm_kcopyd_client_destroy(wc->dm_kcopyd); | |
2044 | ||
2045 | if (wc->dm_io) | |
2046 | dm_io_client_destroy(wc->dm_io); | |
2047 | ||
21ec672e | 2048 | vfree(wc->dirty_bitmap); |
48debafe MP |
2049 | |
2050 | kfree(wc); | |
2051 | } | |
2052 | ||
2053 | static int writecache_ctr(struct dm_target *ti, unsigned argc, char **argv) | |
2054 | { | |
2055 | struct dm_writecache *wc; | |
2056 | struct dm_arg_set as; | |
2057 | const char *string; | |
2058 | unsigned opt_params; | |
2059 | size_t offset, data_size; | |
2060 | int i, r; | |
2061 | char dummy; | |
2062 | int high_wm_percent = HIGH_WATERMARK; | |
2063 | int low_wm_percent = LOW_WATERMARK; | |
2064 | uint64_t x; | |
2065 | struct wc_memory_superblock s; | |
2066 | ||
2067 | static struct dm_arg _args[] = { | |
67aa3ec3 | 2068 | {0, 16, "Invalid number of feature args"}, |
48debafe MP |
2069 | }; |
2070 | ||
2071 | as.argc = argc; | |
2072 | as.argv = argv; | |
2073 | ||
2074 | wc = kzalloc(sizeof(struct dm_writecache), GFP_KERNEL); | |
2075 | if (!wc) { | |
2076 | ti->error = "Cannot allocate writecache structure"; | |
2077 | r = -ENOMEM; | |
2078 | goto bad; | |
2079 | } | |
2080 | ti->private = wc; | |
2081 | wc->ti = ti; | |
2082 | ||
2083 | mutex_init(&wc->lock); | |
3923d485 | 2084 | wc->max_age = MAX_AGE_UNSPECIFIED; |
48debafe MP |
2085 | writecache_poison_lists(wc); |
2086 | init_waitqueue_head(&wc->freelist_wait); | |
2087 | timer_setup(&wc->autocommit_timer, writecache_autocommit_timer, 0); | |
3923d485 | 2088 | timer_setup(&wc->max_age_timer, writecache_max_age_timer, 0); |
48debafe MP |
2089 | |
2090 | for (i = 0; i < 2; i++) { | |
2091 | atomic_set(&wc->bio_in_progress[i], 0); | |
2092 | init_waitqueue_head(&wc->bio_in_progress_wait[i]); | |
2093 | } | |
2094 | ||
2095 | wc->dm_io = dm_io_client_create(); | |
2096 | if (IS_ERR(wc->dm_io)) { | |
2097 | r = PTR_ERR(wc->dm_io); | |
2098 | ti->error = "Unable to allocate dm-io client"; | |
2099 | wc->dm_io = NULL; | |
2100 | goto bad; | |
2101 | } | |
2102 | ||
f87e033b | 2103 | wc->writeback_wq = alloc_workqueue("writecache-writeback", WQ_MEM_RECLAIM, 1); |
48debafe MP |
2104 | if (!wc->writeback_wq) { |
2105 | r = -ENOMEM; | |
2106 | ti->error = "Could not allocate writeback workqueue"; | |
2107 | goto bad; | |
2108 | } | |
2109 | INIT_WORK(&wc->writeback_work, writecache_writeback); | |
2110 | INIT_WORK(&wc->flush_work, writecache_flush_work); | |
2111 | ||
2112 | raw_spin_lock_init(&wc->endio_list_lock); | |
2113 | INIT_LIST_HEAD(&wc->endio_list); | |
2114 | wc->endio_thread = kthread_create(writecache_endio_thread, wc, "writecache_endio"); | |
2115 | if (IS_ERR(wc->endio_thread)) { | |
2116 | r = PTR_ERR(wc->endio_thread); | |
2117 | wc->endio_thread = NULL; | |
2118 | ti->error = "Couldn't spawn endio thread"; | |
2119 | goto bad; | |
2120 | } | |
2121 | wake_up_process(wc->endio_thread); | |
2122 | ||
2123 | /* | |
2124 | * Parse the mode (pmem or ssd) | |
2125 | */ | |
2126 | string = dm_shift_arg(&as); | |
2127 | if (!string) | |
2128 | goto bad_arguments; | |
2129 | ||
2130 | if (!strcasecmp(string, "s")) { | |
2131 | wc->pmem_mode = false; | |
2132 | } else if (!strcasecmp(string, "p")) { | |
2133 | #ifdef DM_WRITECACHE_HAS_PMEM | |
2134 | wc->pmem_mode = true; | |
2135 | wc->writeback_fua = true; | |
2136 | #else | |
2137 | /* | |
2138 | * If the architecture doesn't support persistent memory or | |
2139 | * the kernel doesn't support any DAX drivers, this driver can | |
2140 | * only be used in SSD-only mode. | |
2141 | */ | |
2142 | r = -EOPNOTSUPP; | |
2143 | ti->error = "Persistent memory or DAX not supported on this system"; | |
2144 | goto bad; | |
2145 | #endif | |
2146 | } else { | |
2147 | goto bad_arguments; | |
2148 | } | |
2149 | ||
2150 | if (WC_MODE_PMEM(wc)) { | |
2151 | r = bioset_init(&wc->bio_set, BIO_POOL_SIZE, | |
2152 | offsetof(struct writeback_struct, bio), | |
2153 | BIOSET_NEED_BVECS); | |
2154 | if (r) { | |
2155 | ti->error = "Could not allocate bio set"; | |
2156 | goto bad; | |
2157 | } | |
2158 | } else { | |
2159 | r = mempool_init_kmalloc_pool(&wc->copy_pool, 1, sizeof(struct copy_struct)); | |
2160 | if (r) { | |
2161 | ti->error = "Could not allocate mempool"; | |
2162 | goto bad; | |
2163 | } | |
2164 | } | |
2165 | ||
2166 | /* | |
2167 | * Parse the origin data device | |
2168 | */ | |
2169 | string = dm_shift_arg(&as); | |
2170 | if (!string) | |
2171 | goto bad_arguments; | |
2172 | r = dm_get_device(ti, string, dm_table_get_mode(ti->table), &wc->dev); | |
2173 | if (r) { | |
2174 | ti->error = "Origin data device lookup failed"; | |
2175 | goto bad; | |
2176 | } | |
2177 | ||
2178 | /* | |
2179 | * Parse cache data device (be it pmem or ssd) | |
2180 | */ | |
2181 | string = dm_shift_arg(&as); | |
2182 | if (!string) | |
2183 | goto bad_arguments; | |
2184 | ||
2185 | r = dm_get_device(ti, string, dm_table_get_mode(ti->table), &wc->ssd_dev); | |
2186 | if (r) { | |
2187 | ti->error = "Cache data device lookup failed"; | |
2188 | goto bad; | |
2189 | } | |
2190 | wc->memory_map_size = i_size_read(wc->ssd_dev->bdev->bd_inode); | |
2191 | ||
48debafe MP |
2192 | /* |
2193 | * Parse the cache block size | |
2194 | */ | |
2195 | string = dm_shift_arg(&as); | |
2196 | if (!string) | |
2197 | goto bad_arguments; | |
2198 | if (sscanf(string, "%u%c", &wc->block_size, &dummy) != 1 || | |
2199 | wc->block_size < 512 || wc->block_size > PAGE_SIZE || | |
2200 | (wc->block_size & (wc->block_size - 1))) { | |
2201 | r = -EINVAL; | |
2202 | ti->error = "Invalid block size"; | |
2203 | goto bad; | |
2204 | } | |
31b22120 MP |
2205 | if (wc->block_size < bdev_logical_block_size(wc->dev->bdev) || |
2206 | wc->block_size < bdev_logical_block_size(wc->ssd_dev->bdev)) { | |
2207 | r = -EINVAL; | |
2208 | ti->error = "Block size is smaller than device logical block size"; | |
2209 | goto bad; | |
2210 | } | |
48debafe MP |
2211 | wc->block_size_bits = __ffs(wc->block_size); |
2212 | ||
2213 | wc->max_writeback_jobs = MAX_WRITEBACK_JOBS; | |
2214 | wc->autocommit_blocks = !WC_MODE_PMEM(wc) ? AUTOCOMMIT_BLOCKS_SSD : AUTOCOMMIT_BLOCKS_PMEM; | |
2215 | wc->autocommit_jiffies = msecs_to_jiffies(AUTOCOMMIT_MSEC); | |
2216 | ||
2217 | /* | |
2218 | * Parse optional arguments | |
2219 | */ | |
2220 | r = dm_read_arg_group(_args, &as, &opt_params, &ti->error); | |
2221 | if (r) | |
2222 | goto bad; | |
2223 | ||
2224 | while (opt_params) { | |
2225 | string = dm_shift_arg(&as), opt_params--; | |
d284f824 MP |
2226 | if (!strcasecmp(string, "start_sector") && opt_params >= 1) { |
2227 | unsigned long long start_sector; | |
2228 | string = dm_shift_arg(&as), opt_params--; | |
2229 | if (sscanf(string, "%llu%c", &start_sector, &dummy) != 1) | |
2230 | goto invalid_optional; | |
2231 | wc->start_sector = start_sector; | |
054bee16 | 2232 | wc->start_sector_set = true; |
d284f824 MP |
2233 | if (wc->start_sector != start_sector || |
2234 | wc->start_sector >= wc->memory_map_size >> SECTOR_SHIFT) | |
2235 | goto invalid_optional; | |
2236 | } else if (!strcasecmp(string, "high_watermark") && opt_params >= 1) { | |
48debafe MP |
2237 | string = dm_shift_arg(&as), opt_params--; |
2238 | if (sscanf(string, "%d%c", &high_wm_percent, &dummy) != 1) | |
2239 | goto invalid_optional; | |
2240 | if (high_wm_percent < 0 || high_wm_percent > 100) | |
2241 | goto invalid_optional; | |
054bee16 | 2242 | wc->high_wm_percent_value = high_wm_percent; |
48debafe MP |
2243 | wc->high_wm_percent_set = true; |
2244 | } else if (!strcasecmp(string, "low_watermark") && opt_params >= 1) { | |
2245 | string = dm_shift_arg(&as), opt_params--; | |
2246 | if (sscanf(string, "%d%c", &low_wm_percent, &dummy) != 1) | |
2247 | goto invalid_optional; | |
2248 | if (low_wm_percent < 0 || low_wm_percent > 100) | |
2249 | goto invalid_optional; | |
054bee16 | 2250 | wc->low_wm_percent_value = low_wm_percent; |
48debafe MP |
2251 | wc->low_wm_percent_set = true; |
2252 | } else if (!strcasecmp(string, "writeback_jobs") && opt_params >= 1) { | |
2253 | string = dm_shift_arg(&as), opt_params--; | |
2254 | if (sscanf(string, "%u%c", &wc->max_writeback_jobs, &dummy) != 1) | |
2255 | goto invalid_optional; | |
2256 | wc->max_writeback_jobs_set = true; | |
2257 | } else if (!strcasecmp(string, "autocommit_blocks") && opt_params >= 1) { | |
2258 | string = dm_shift_arg(&as), opt_params--; | |
2259 | if (sscanf(string, "%u%c", &wc->autocommit_blocks, &dummy) != 1) | |
2260 | goto invalid_optional; | |
2261 | wc->autocommit_blocks_set = true; | |
2262 | } else if (!strcasecmp(string, "autocommit_time") && opt_params >= 1) { | |
2263 | unsigned autocommit_msecs; | |
2264 | string = dm_shift_arg(&as), opt_params--; | |
2265 | if (sscanf(string, "%u%c", &autocommit_msecs, &dummy) != 1) | |
2266 | goto invalid_optional; | |
2267 | if (autocommit_msecs > 3600000) | |
2268 | goto invalid_optional; | |
2269 | wc->autocommit_jiffies = msecs_to_jiffies(autocommit_msecs); | |
054bee16 | 2270 | wc->autocommit_time_value = autocommit_msecs; |
48debafe | 2271 | wc->autocommit_time_set = true; |
3923d485 MP |
2272 | } else if (!strcasecmp(string, "max_age") && opt_params >= 1) { |
2273 | unsigned max_age_msecs; | |
2274 | string = dm_shift_arg(&as), opt_params--; | |
2275 | if (sscanf(string, "%u%c", &max_age_msecs, &dummy) != 1) | |
2276 | goto invalid_optional; | |
2277 | if (max_age_msecs > 86400000) | |
2278 | goto invalid_optional; | |
2279 | wc->max_age = msecs_to_jiffies(max_age_msecs); | |
054bee16 MP |
2280 | wc->max_age_set = true; |
2281 | wc->max_age_value = max_age_msecs; | |
93de44eb | 2282 | } else if (!strcasecmp(string, "cleaner")) { |
054bee16 | 2283 | wc->cleaner_set = true; |
93de44eb | 2284 | wc->cleaner = true; |
48debafe MP |
2285 | } else if (!strcasecmp(string, "fua")) { |
2286 | if (WC_MODE_PMEM(wc)) { | |
2287 | wc->writeback_fua = true; | |
2288 | wc->writeback_fua_set = true; | |
2289 | } else goto invalid_optional; | |
2290 | } else if (!strcasecmp(string, "nofua")) { | |
2291 | if (WC_MODE_PMEM(wc)) { | |
2292 | wc->writeback_fua = false; | |
2293 | wc->writeback_fua_set = true; | |
2294 | } else goto invalid_optional; | |
2295 | } else { | |
2296 | invalid_optional: | |
2297 | r = -EINVAL; | |
2298 | ti->error = "Invalid optional argument"; | |
2299 | goto bad; | |
2300 | } | |
2301 | } | |
2302 | ||
2303 | if (high_wm_percent < low_wm_percent) { | |
2304 | r = -EINVAL; | |
2305 | ti->error = "High watermark must be greater than or equal to low watermark"; | |
2306 | goto bad; | |
2307 | } | |
2308 | ||
d284f824 | 2309 | if (WC_MODE_PMEM(wc)) { |
a4662458 MS |
2310 | if (!dax_synchronous(wc->ssd_dev->dax_dev)) { |
2311 | r = -EOPNOTSUPP; | |
2312 | ti->error = "Asynchronous persistent memory not supported as pmem cache"; | |
2313 | goto bad; | |
2314 | } | |
2315 | ||
d284f824 MP |
2316 | r = persistent_memory_claim(wc); |
2317 | if (r) { | |
2318 | ti->error = "Unable to map persistent memory for cache"; | |
2319 | goto bad; | |
2320 | } | |
2321 | } else { | |
48debafe MP |
2322 | size_t n_blocks, n_metadata_blocks; |
2323 | uint64_t n_bitmap_bits; | |
2324 | ||
d284f824 MP |
2325 | wc->memory_map_size -= (uint64_t)wc->start_sector << SECTOR_SHIFT; |
2326 | ||
48debafe MP |
2327 | bio_list_init(&wc->flush_list); |
2328 | wc->flush_thread = kthread_create(writecache_flush_thread, wc, "dm_writecache_flush"); | |
2329 | if (IS_ERR(wc->flush_thread)) { | |
2330 | r = PTR_ERR(wc->flush_thread); | |
2331 | wc->flush_thread = NULL; | |
e8ea141a | 2332 | ti->error = "Couldn't spawn flush thread"; |
48debafe MP |
2333 | goto bad; |
2334 | } | |
2335 | wake_up_process(wc->flush_thread); | |
2336 | ||
2337 | r = calculate_memory_size(wc->memory_map_size, wc->block_size, | |
2338 | &n_blocks, &n_metadata_blocks); | |
2339 | if (r) { | |
2340 | ti->error = "Invalid device size"; | |
2341 | goto bad; | |
2342 | } | |
2343 | ||
2344 | n_bitmap_bits = (((uint64_t)n_metadata_blocks << wc->block_size_bits) + | |
2345 | BITMAP_GRANULARITY - 1) / BITMAP_GRANULARITY; | |
2346 | /* this is limitation of test_bit functions */ | |
2347 | if (n_bitmap_bits > 1U << 31) { | |
2348 | r = -EFBIG; | |
2349 | ti->error = "Invalid device size"; | |
2350 | goto bad; | |
2351 | } | |
2352 | ||
2353 | wc->memory_map = vmalloc(n_metadata_blocks << wc->block_size_bits); | |
2354 | if (!wc->memory_map) { | |
2355 | r = -ENOMEM; | |
2356 | ti->error = "Unable to allocate memory for metadata"; | |
2357 | goto bad; | |
2358 | } | |
2359 | ||
2360 | wc->dm_kcopyd = dm_kcopyd_client_create(&dm_kcopyd_throttle); | |
2361 | if (IS_ERR(wc->dm_kcopyd)) { | |
2362 | r = PTR_ERR(wc->dm_kcopyd); | |
2363 | ti->error = "Unable to allocate dm-kcopyd client"; | |
2364 | wc->dm_kcopyd = NULL; | |
2365 | goto bad; | |
2366 | } | |
2367 | ||
2368 | wc->metadata_sectors = n_metadata_blocks << (wc->block_size_bits - SECTOR_SHIFT); | |
2369 | wc->dirty_bitmap_size = (n_bitmap_bits + BITS_PER_LONG - 1) / | |
2370 | BITS_PER_LONG * sizeof(unsigned long); | |
2371 | wc->dirty_bitmap = vzalloc(wc->dirty_bitmap_size); | |
2372 | if (!wc->dirty_bitmap) { | |
2373 | r = -ENOMEM; | |
2374 | ti->error = "Unable to allocate dirty bitmap"; | |
2375 | goto bad; | |
2376 | } | |
2377 | ||
31b22120 | 2378 | r = writecache_read_metadata(wc, wc->block_size >> SECTOR_SHIFT); |
48debafe | 2379 | if (r) { |
31b22120 | 2380 | ti->error = "Unable to read first block of metadata"; |
48debafe MP |
2381 | goto bad; |
2382 | } | |
2383 | } | |
2384 | ||
ec6347bb | 2385 | r = copy_mc_to_kernel(&s, sb(wc), sizeof(struct wc_memory_superblock)); |
48debafe MP |
2386 | if (r) { |
2387 | ti->error = "Hardware memory error when reading superblock"; | |
2388 | goto bad; | |
2389 | } | |
2390 | if (!le32_to_cpu(s.magic) && !le32_to_cpu(s.version)) { | |
2391 | r = init_memory(wc); | |
2392 | if (r) { | |
2393 | ti->error = "Unable to initialize device"; | |
2394 | goto bad; | |
2395 | } | |
ec6347bb DW |
2396 | r = copy_mc_to_kernel(&s, sb(wc), |
2397 | sizeof(struct wc_memory_superblock)); | |
48debafe MP |
2398 | if (r) { |
2399 | ti->error = "Hardware memory error when reading superblock"; | |
2400 | goto bad; | |
2401 | } | |
2402 | } | |
2403 | ||
2404 | if (le32_to_cpu(s.magic) != MEMORY_SUPERBLOCK_MAGIC) { | |
2405 | ti->error = "Invalid magic in the superblock"; | |
2406 | r = -EINVAL; | |
2407 | goto bad; | |
2408 | } | |
2409 | ||
2410 | if (le32_to_cpu(s.version) != MEMORY_SUPERBLOCK_VERSION) { | |
2411 | ti->error = "Invalid version in the superblock"; | |
2412 | r = -EINVAL; | |
2413 | goto bad; | |
2414 | } | |
2415 | ||
2416 | if (le32_to_cpu(s.block_size) != wc->block_size) { | |
2417 | ti->error = "Block size does not match superblock"; | |
2418 | r = -EINVAL; | |
2419 | goto bad; | |
2420 | } | |
2421 | ||
2422 | wc->n_blocks = le64_to_cpu(s.n_blocks); | |
2423 | ||
2424 | offset = wc->n_blocks * sizeof(struct wc_memory_entry); | |
2425 | if (offset / sizeof(struct wc_memory_entry) != le64_to_cpu(sb(wc)->n_blocks)) { | |
2426 | overflow: | |
2427 | ti->error = "Overflow in size calculation"; | |
2428 | r = -EINVAL; | |
2429 | goto bad; | |
2430 | } | |
2431 | offset += sizeof(struct wc_memory_superblock); | |
2432 | if (offset < sizeof(struct wc_memory_superblock)) | |
2433 | goto overflow; | |
2434 | offset = (offset + wc->block_size - 1) & ~(size_t)(wc->block_size - 1); | |
2435 | data_size = wc->n_blocks * (size_t)wc->block_size; | |
2436 | if (!offset || (data_size / wc->block_size != wc->n_blocks) || | |
2437 | (offset + data_size < offset)) | |
2438 | goto overflow; | |
2439 | if (offset + data_size > wc->memory_map_size) { | |
2440 | ti->error = "Memory area is too small"; | |
2441 | r = -EINVAL; | |
2442 | goto bad; | |
2443 | } | |
2444 | ||
2445 | wc->metadata_sectors = offset >> SECTOR_SHIFT; | |
2446 | wc->block_start = (char *)sb(wc) + offset; | |
2447 | ||
2448 | x = (uint64_t)wc->n_blocks * (100 - high_wm_percent); | |
2449 | x += 50; | |
2450 | do_div(x, 100); | |
2451 | wc->freelist_high_watermark = x; | |
2452 | x = (uint64_t)wc->n_blocks * (100 - low_wm_percent); | |
2453 | x += 50; | |
2454 | do_div(x, 100); | |
2455 | wc->freelist_low_watermark = x; | |
2456 | ||
93de44eb MP |
2457 | if (wc->cleaner) |
2458 | activate_cleaner(wc); | |
2459 | ||
48debafe MP |
2460 | r = writecache_alloc_entries(wc); |
2461 | if (r) { | |
2462 | ti->error = "Cannot allocate memory"; | |
2463 | goto bad; | |
2464 | } | |
2465 | ||
2466 | ti->num_flush_bios = 1; | |
2467 | ti->flush_supported = true; | |
2468 | ti->num_discard_bios = 1; | |
2469 | ||
2470 | if (WC_MODE_PMEM(wc)) | |
2471 | persistent_memory_flush_cache(wc->memory_map, wc->memory_map_size); | |
2472 | ||
2473 | return 0; | |
2474 | ||
2475 | bad_arguments: | |
2476 | r = -EINVAL; | |
2477 | ti->error = "Bad arguments"; | |
2478 | bad: | |
2479 | writecache_dtr(ti); | |
2480 | return r; | |
2481 | } | |
2482 | ||
2483 | static void writecache_status(struct dm_target *ti, status_type_t type, | |
2484 | unsigned status_flags, char *result, unsigned maxlen) | |
2485 | { | |
2486 | struct dm_writecache *wc = ti->private; | |
2487 | unsigned extra_args; | |
2488 | unsigned sz = 0; | |
48debafe MP |
2489 | |
2490 | switch (type) { | |
2491 | case STATUSTYPE_INFO: | |
2492 | DMEMIT("%ld %llu %llu %llu", writecache_has_error(wc), | |
2493 | (unsigned long long)wc->n_blocks, (unsigned long long)wc->freelist_size, | |
2494 | (unsigned long long)wc->writeback_size); | |
2495 | break; | |
2496 | case STATUSTYPE_TABLE: | |
2497 | DMEMIT("%c %s %s %u ", WC_MODE_PMEM(wc) ? 'p' : 's', | |
2498 | wc->dev->name, wc->ssd_dev->name, wc->block_size); | |
2499 | extra_args = 0; | |
054bee16 | 2500 | if (wc->start_sector_set) |
9ff07e7d | 2501 | extra_args += 2; |
054bee16 | 2502 | if (wc->high_wm_percent_set) |
48debafe | 2503 | extra_args += 2; |
054bee16 | 2504 | if (wc->low_wm_percent_set) |
48debafe MP |
2505 | extra_args += 2; |
2506 | if (wc->max_writeback_jobs_set) | |
2507 | extra_args += 2; | |
2508 | if (wc->autocommit_blocks_set) | |
2509 | extra_args += 2; | |
2510 | if (wc->autocommit_time_set) | |
2511 | extra_args += 2; | |
054bee16 | 2512 | if (wc->max_age_set) |
e5d41cbc | 2513 | extra_args += 2; |
054bee16 | 2514 | if (wc->cleaner_set) |
93de44eb | 2515 | extra_args++; |
48debafe MP |
2516 | if (wc->writeback_fua_set) |
2517 | extra_args++; | |
2518 | ||
2519 | DMEMIT("%u", extra_args); | |
054bee16 | 2520 | if (wc->start_sector_set) |
9ff07e7d | 2521 | DMEMIT(" start_sector %llu", (unsigned long long)wc->start_sector); |
054bee16 MP |
2522 | if (wc->high_wm_percent_set) |
2523 | DMEMIT(" high_watermark %u", wc->high_wm_percent_value); | |
2524 | if (wc->low_wm_percent_set) | |
2525 | DMEMIT(" low_watermark %u", wc->low_wm_percent_value); | |
48debafe MP |
2526 | if (wc->max_writeback_jobs_set) |
2527 | DMEMIT(" writeback_jobs %u", wc->max_writeback_jobs); | |
2528 | if (wc->autocommit_blocks_set) | |
2529 | DMEMIT(" autocommit_blocks %u", wc->autocommit_blocks); | |
2530 | if (wc->autocommit_time_set) | |
054bee16 MP |
2531 | DMEMIT(" autocommit_time %u", wc->autocommit_time_value); |
2532 | if (wc->max_age_set) | |
2533 | DMEMIT(" max_age %u", wc->max_age_value); | |
2534 | if (wc->cleaner_set) | |
93de44eb | 2535 | DMEMIT(" cleaner"); |
48debafe MP |
2536 | if (wc->writeback_fua_set) |
2537 | DMEMIT(" %sfua", wc->writeback_fua ? "" : "no"); | |
2538 | break; | |
2539 | } | |
2540 | } | |
2541 | ||
2542 | static struct target_type writecache_target = { | |
2543 | .name = "writecache", | |
054bee16 | 2544 | .version = {1, 4, 0}, |
48debafe MP |
2545 | .module = THIS_MODULE, |
2546 | .ctr = writecache_ctr, | |
2547 | .dtr = writecache_dtr, | |
2548 | .status = writecache_status, | |
2549 | .postsuspend = writecache_suspend, | |
2550 | .resume = writecache_resume, | |
2551 | .message = writecache_message, | |
2552 | .map = writecache_map, | |
2553 | .end_io = writecache_end_io, | |
2554 | .iterate_devices = writecache_iterate_devices, | |
2555 | .io_hints = writecache_io_hints, | |
2556 | }; | |
2557 | ||
2558 | static int __init dm_writecache_init(void) | |
2559 | { | |
2560 | int r; | |
2561 | ||
2562 | r = dm_register_target(&writecache_target); | |
2563 | if (r < 0) { | |
2564 | DMERR("register failed %d", r); | |
2565 | return r; | |
2566 | } | |
2567 | ||
2568 | return 0; | |
2569 | } | |
2570 | ||
2571 | static void __exit dm_writecache_exit(void) | |
2572 | { | |
2573 | dm_unregister_target(&writecache_target); | |
2574 | } | |
2575 | ||
2576 | module_init(dm_writecache_init); | |
2577 | module_exit(dm_writecache_exit); | |
2578 | ||
2579 | MODULE_DESCRIPTION(DM_NAME " writecache target"); | |
2580 | MODULE_AUTHOR("Mikulas Patocka <dm-devel@redhat.com>"); | |
2581 | MODULE_LICENSE("GPL"); |